Guest - Not logged in 

Reviews > Lighting > Headlamps - LED > Essential Gear K2 Focus Headlamp > Test Report by Kurt Papke

Essential Gear K2 Focus headlamp

Test Series by Kurt Papke

Initial Report - April 5, 2009

Field Report - June 16, 2009

Long Term Report - August 11, 2009

Tester Information

Name: Kurt Papke
Age: 55
Gender: Male
Height: 6' 4" (193 cm)
Weight: 220 lbs (100 kg)
Email address: kwpapke at gmail dot com
City, State, Country: Minneapolis, Minnesota USA
Backpacking background: mostly in Minnesota - I have hiked all of the Superior Hiking Trail and Border Route.  This last year included hiking in Michigan, Wisconsin, Utah, Colorado, south and North Dakota and Oregon.  My preferred/typical backpack trip is one week, mostly in the Spring/Fall seasons, but I started doing more winter camping this year.  I always carry several lights with me when backpacking, including a headlamp.

Initial Report

The Essential Gear K2 Focus headlamp (hereafter referred to as the "K2") is a head-mounted LED lamp.  It is distinctive from many LED backpacker headlamps in several respects:
  1. It is powered by AA batteries instead of the more common AAA size.  Because of the greater weight of AA batteries, they are contained in a separate case mounted on the rear of the head strap for balance.  A cable routes power from the rear battery pack to the front located lamp.
  2. It has a variable focal length.  The beam can be focused tightly for a bright, narrow beam, or widely for broader illumination that is less intense.
  3. It has three colored (red, green, blue) LEDs in addition to the white LED.  These colored LEDs are intended to reduce interference with night vision.
  4. The white K2 LED has a very bright rating of 85 lumens.  This LED likely has a substantial current draw, hence the inclusion of AA batteries.
  5. The back of the battery pack has an amber light which makes the wearer more visible from the rear at night.

Product Information

The manufacturer did not provide the battery type for the information in the following table.  All of my measurements were made with Duracell alkaline cells shipped with the unit.

Manufacturer: Essential Gear
Year of manufacture: 2009
US $ 55.00
Manufacturer website:

(Product label)
Battery Case:
3.2 x 2 x 1 in
(82 x 51 x 29 mm)
2.8 x 2 x 1.7 in
(72 x 53 x 43 mm)
Battery Case:
3.2 x 2 x 1 in
(85 x 51 x 29 mm)
2.8 x 2 x 1.7 in
(72 x 53 x 43 mm)
Battery case:
3.2 x 1.9 x 1.1 in
(81 x 49 x 29 mm)
2.8 x 2 x 1.7 in
(72 x 50 x 43 mm)
Weight with battery:
5 oz (155 g)
5 oz (155 g)
7.1 oz (202 g)
without batteries:
4.6 oz (128 g)
Battery life:
16 hours high [Max output: 7 hours]
32 hours low
48 hours flashing
5mm (red, green, blue) LEDs:
240 hours
500 hours red LED flashing
16 hours high
32 hours low
48 hours flashing
5mm (red, green, blue) LEDs:
240 hours
500 hours red LED flashing
LED Brightness:
White: 85 lumens max
Red/Green/Blue: 1.8 lumens
White: 85 lumens max
Red/Green/Blue: 1.8 lumens
Rear: 1 lumen
Not measured

Note the discrepancy in the metric listed measurements between the packaging and the website in RED.  The product label is closer to the listed inch dimensions.

Note that the weights given by the manufacturer seem to be closer to what I measure without batteries, though the documentation specifically says it is WITH batteries.

A brief note on the brightness specifications
: the numbers given by the manufacturer do not necessarily imply that the white light will be 47 (85/1.8) times "brighter" than the color LEDs.  A lumen is a measurement of the total light output of a device, but the illumination of a surface (like the trail in front of us as we hike) also depends on how much area that light is spread out over.  In fact, that is precisely the object of the focus control on the K2: I can choose to illuminate a small area very brightly, or spread the light out over a larger area and get a dimmer illumination. I should actually see more than a 47:1 difference in illumination between the colored LEDs and the focused white LED  because the white light is concentrated in a small cone, but the colored light is spread out over a wide area.  Illumination is measured in foot-candles (lux), and can be measured with a light meter.

LED modes: All of the LEDs can be turned, on, off and set to flash.  The white LED is the only one that has a brightness control: it has a high and low mode.

The headlamp is stated to be "water resistant".


The lamp came packaged with a double-sided 4-color insert visible through the plastic wrap.  The insert contained the specifications and operating instructions.

The instructions for inserting the (supplied) batteries were clear and I had no problems installing them.  I was happy to see no tools were required; I liked the twist-lock closure.

The instructions for light operation are a little terse: "Press 3 seconds for Independent Operation of K2 LED or 05mm LEDs, Press Off if stays at Any Mode over 3 seconds".  It is actually a little more complicated than that -- see next section.

Light Switch

One of my frustrations with the many lamps I own is the confusion I often encounter with operating them.  The manufacturers keep the number of control switches to a minimum (often just one) to keep the cost and weight down and to minimize places where water might enter.  As the number of options increases it gets more difficult to understand and remember how to do it: do I press multiple times, press and hold, etc.  As an attempt to document how this lamp works, see the following state chart:
K2 Focus Headlamp State Chart

How to read this chart: if the lamp button is initially pressed and held for less than three seconds, the K2 white LED comes on at high power.  Subsequent short presses (< 3 seconds) cause the lamp to first dim, then blink, then turn off.

If the lamp is in "White Mode", and the button is pressed and held for >3 seconds the blue LED is lit.  If the button is pressed again before another 3 seconds elapses, the green LED is lit, and on to red and blinking red.  If any of the color LEDs is lit for more than 3 seconds, another button press turns the LED off.  Any time the lamp is in "Color Mode", pressing and holding the button for >3 seconds transitions to white mode and the white LED is brightly lit.

One thing that is apparent from the diagram is that in "White Mode", if the lamp is turned off it always comes back on bright.  I typically use my lamps in low power mode to conserve batteries.  I wish the K2 Focus lamp remembered that it was in low or blink when last used.  Similarly, when using the color LEDs if turned off the color always reverts to blue.  I wish it remembered the color I was using when turned off.

rear lamp and controlThe control for the rear light as shown in the photo at left is much simpler: it operates similar to the "White Mode" but there is only one intensity.  The button is a little bit smaller than the front lamp control.

Focus Control

focus controlThe width and intensity of the white beam is controlled by a slide on the bottom of the lamp.  It is marked "1X" to "4X".  I found the control easy to locate and use.

Here's two pictures of the lamp projected on a wall from about 10 ft (3.3 m):

zoomed outzoomed in

The diameter of the circle on the left is about twice that of the one on the right, so it has about 4x the area.  It will be interesting to see on the trail how I end up using the focus and how effective it is in the field to zoom in/out on areas of interest.

Initial Use

Lamp on headI played around with the lamp the first night after I received it.  It seemed like the front lamp switch was difficult for my finger to find.  It is not particularly big, nor does it protrude up very far.  My other lamp has a switch many times the size of this one.

The lamp also can be tilted up or down.  The tilt is easily operated and there is a ratchet to keep the lamp from slipping down from vibration.

The lamp fits comfortably on my head, despite its heft.  It seems that the balance from having the battery in the back and the lamp in the front makes the relatively heavy weight of the lamp from the 3 AA batteries quite bearable.


I am excited to use this lamp in the field.  I have been looking for a headlamp for some time that takes AA batteries for two reasons:
  1. They perform much better in the cold Minnesota winters.  Even lithium AAA batteries discharge quickly in frigid weather.
  2. I have several other devices that use AA batteries: GPS, digital camera, and most recently a wood-fired stove that has a draft fan.  I want to standardize on AA batteries to allow common spares and cannibalization in emergencies.
It took me a few minutes to learn to operate the controls, but now that I understand it I appreciate the flexibility of its operation.

This concludes my Initial Report.

Field Report

Test Conditions

March 28-April 4, 2009 April 23-26, 2009 May 1-3, 2009 May 20-24, 2009 June 11-14, 2009
Ozark Trail in south-central Missouri located in the Mark Twain National Forest
North Country Trail (NCT), Heritage section in northern Wisconsin Superior Hiking Trail (SHT) between Split Rock and Tettegouche state parks.
This was a car-camping trip, so only short sections of the trail were hiked in and between the parks.
Kekekabic Trail through the Boundary Waters Canoe Area Wilderness (BWCAW) of northern Minnesota. North Country Trail (NCT), Chequamegon section in northern Wisconsin
925 ft to 1650 ft (280 m to 500 m) 12500 to 1800 ft (380 to 550 m) 650 ft to 1500 ft (200 m to 460 m) 1450 ft to 2000 ft (440 m to 610 m) 1050 ft to 1650 ft
(320 m to 500 m)
Heavily forested with oak and hickory.  Many streams, one lake.  Continual climb & descent of Ozark mountains. Heavily forested mix of deciduous and pine.  Streams, rivers, waterfalls, one beaver dam crossing.  Granite outcroppings. Heavily forested mix of birch and aspen.  Day 1 and 2 were ascent/descent trips, Day 3 was constant up-and-down. Burned and blowdown areas to dense forests of poplar and spruce. Heavily forested with maple and pine.  Streams, lakes, bogs and beaver dams.
Coldest night time low was 26 F (-3 C), warmest daytime high was about 70F (21 C).  Snowed the first night, had a whole afternoon of rain on day five, rain showers off and on for several days.
Nightly lows near freezing, daytime highs ranging from 45-65 F (7-18 C) Nightly lows just below freezing, daytime highs ranging from 45-65 F (7-18 C).  Day 3 was sunny. Lowest nighttime temperature was 29 F (-2 C), highest daytime temperature of 80 F (27 C) Coldest nighttime low was 41 F (5 C), daytime highs around 74 F (23 C), very light winds.  Mostly sunny with rain shower June 13.


Ozark Trail

Before departing on this trip I packed 6 spare Lithium AA batteries.  I was happy that ALL my electric-powered devices on this trip (headlamp, camera, GPS and wood stove) used AA batteries.  My spares would be ready regardless of which devices ran down their batteries.

Packing: I threw the lamp in the bottom of a side pocket in my backpack and jammed stuff on top of it all week long.  It never turned on accidentally, never got in the way, and suffered no ill effects from being exposed to rain and damp weather.

On this one-week backpacking trip I used the colored LEDs on the headlamp every evening for my nightly tree-watering excursions.  One of the first things I noticed was "why does the blue light come on first?"  After all, don't photographers use a red lamp in the darkroom, and isn't it a red lamp that minimizes loss of night vision?  Perhaps the designers thought that the red LED would be useful in flashing mode as an emergency beacon, and to be consistent with the white mode the red LED had to be last in the sequence.  I was also surprised by how focused the color LEDs were despite the fact they do not have an accessory lens to focus the beam.  Obviously, a lens is built directly into the LEDs, and they are quite effective.

It did seem that all the color LEDs did a good job of retaining my night vision.  After I turned the lamp off I was able to immediately see well at night.  There is no doubt a difference between colors in night vision retention, but it was beyond my ability to detect the difference in normal operation.

To keep the headlamp accessible I hung it from the ridge line of my shelter, the battery pack on one side of the line, the lamp on the other, and the strap looped over the top.  This worked well: the lamp stayed in place, was easy to reach, and the light pointed down for task illumination.  I did find the on/off button difficult to find with my fingers in the dark.  It is not a problem when the lamp is on my head as it is positioned right at the top, but when the headlamp is not on my head I fumbled for some seconds to find the button.  To me, the button seems small and is not raised enough from the lamp housing to create a good tactile sense.

I tried using the various colors, and I didn't notice an appreciable different in visibility with the various colors until the night it rained.  The blue and green lights really showed wet versus dry vegetation, whereas with the red LED the two were indistinguishable.

I used the bright white light every morning to read my thermometer.  As I've grown older my reading vision has diminished and I now need reading glasses, but with the bright K2 LED on High with the beam focused as narrow as possible I could read the temperature without my glasses.  Nice.

Night falls on the Ozark Trail

On my last morning on the trail I packed up and hiked back to my car before the sun was up.  I used the white light on High with the wide beam for breaking camp.  I found that while breaking camp I preferred the wider to the narrow beam because it gave me a wider field of view of my gear.  On the hike back to the car the sky was starting to lighten up, so I switched to the narrow beam to illuminate the treadway.  The light worked great for that, but I found the "bouncing" of the narrow beam somewhat distracting, and preferred a wider but less intense beam.

NCT - April

I continued to use the headlamp for my nightly tree watering outings.  I find that I prefer the red LED for this purpose, and I wish it was the first selection in color mode.  The green and blue colors just seem bizarre to me.

On night 3 of this trip I pitched my tent about 100 ft (30 m) from the main campsite as all the tent pads there had been taken by my compatriots before I set up.  We stayed up until well after dark with a campfire, and I used the lamp to follow the trail back to my tent.  I found I preferred the wide beam setting for this purpose to light up the width of the trail.

My fellow campers were astounded at how bright this light was.  It made their headlamps look like a weak glow.


This was a car camping trip (Finland State Forest campground) and the headlamp was packed in the pocket of a duffel bag instead of in my backpack.  When I arrived at the campground and opened up the pocket, I noticed the blue LED was on, but the lamp was not on when I packed it the night before.  I could only conclude that bouncing around in the pocket had bumped the on/off switch causing the lamp to inadvertently turn on.  This is not good, as it could result in battery drain.  Clearly, the switch should be designed to prevent this from happening.

I used the light in the evenings as we returned back to our campsite both nights very late.  On the second evening I had to take an evening stroll to the latrine in the dark, which was about a 500 ft (150 m) walk down a dark snow-covered road.  I experimented with various LED colors to see which one worked better.  One thing I noticed is that the blue LED will not light up a yellow reflective sign.  This makes sense, as yellow reflects only green and red.  When I got back to my car I noticed that the red LED was the only one that would light up the red reflectors on my car, and that also makes sense.

On the second evening a camper pulled in to the neighboring spot and began to attempt to set up her tent in the dark.  I offered her the use of the headlamp, which she gratefully accepted saying how silly of her to forget her lamp.  She really appreciated the bright K2 LED and completed setting up her tent with no difficulties using the headlamp.  It was quite interesting to watch someone else use the headlamp - it really is very bright and effective at illuminating a large work area.

Kekekabic Trail

Morning mist
Morning mist by the Boundary Waters Kekekabic Trail

By late May the days start getting pretty long near the Canadian border.  The sky did not get dark until 9PM, and began getting light at about 4AM.  The only use on this trip for the headlamp was illuminating my night time tree watering excursions, which I did with the blue LED to conserve battery power.  The headlamp handled this task well.  On this trip I began to tire a bit of the weight of the headlamp, and to not enjoy the weight distributed between the lamp unit and battery pack.  It just seemed to be a lot more weight penalty than the lighting value I was actually using.  On the other hand I was getting used to using the non-red LED lights - they no longer seemed bizarre to me.  In fact, they seemed brighter than the red light.

NCT - June

The headlamp got more use on this trip despite the long day length as the people I was hiking with liked to stay up late around a campfire and talk.  I loaned the headlamp on the first night to a fellow camper who had to hike the 0.4 miles (0.6 km) to the parking lot and back after dark.  It was useful to watch someone else use the lamp at night on the trail hiking with several other people with headlamps.  The K2 was incredibly brighter than any other headlamp in the group.

I noticed on this trip that the light switch is back-illuminated only when the red LED is used.  The back-light is handy for finding the switch to turn the light off, and it is logical that only the red LED illuminates the switch as it is positioned directly beneath it.


The K2 Focus headlamp provides fantastic illumination, but at the cost of weight.  My feeling so far is that this is a lamp for my winter use when there are more hours of darkness and larger batteries are needed due to cold weather impact on their performance.  I really wish I had been testing this lamp in January and February.  The battery life has been good so far - after five backpacking trips I am still on the original cells.

  1. Very bright high beam
  2. Variable beam width for detailed task lighting versus wider trail illumination
  3. Color LED's retain night vision but are bright enough to manoeuvre with
  4. AA batteries for commonality and long burn times
Areas for improvement:
  1. On/off switch for the lamp is hard to find when the headlamp is not worn on the head
  2. Too easy for jostling to accidentally turn the lamp on and drain the battery
  3. I would prefer the red LED be the first setting in color mode
  4. Quite heavy, especially with the 3 AA batteries

Long Term Report

Test Conditions

July 11-12, 2009 August 1-2, 2009
Mt Lemmon just north of Tucson - Mt Lemmon Trail (section of Arizona Trail) Mt Lemmon, Wilderness of Rocks Trail
7450 ft to 9100 ft
(2271 m to 2774 m)
7000 ft to 8100 ft
(2100 m to 2500 m)
Mountain meadows, rocky ridges and trail.  All descent/ascent, almost no level hiking. Pine forests, rocky trail and outcroppings
Nighttime low of 60F (15 C), daytime high at lower altitude of 88 F (31 C) Nighttime low of 60F (15 C), daytime high at lower altitude of 90 F (32 C)


Mt Lemmon - Mt Lemmon Trail

On July 5 I moved to Tucson, Arizona.  The K2 headlamp survived the move with no ill effects.  This locale should allow a bit better testing of the headlamp because Arizona does not observe daylight savings time, so it gets dark at least an hour earlier than is typical elsewhere in the U.S. during the summer months.  Also day length is not as extended during the summer in southern latitudes.

7:30 sunset on Mt Lemmon
7:30 PM sunset on Mt Lemmon, Oro Valley below

Sure enough, on my first Arizona backpacking outing it got pretty dark at about 8:30PM.  The above photo shows the sunset about an hour earlier.  I had to break out the headlamp for final camp chores, which it worked well for.  It was also used during the usual nighttime excursions with no issues.

Mt Lemmon - Wilderness of Rocks Trail

The headlamp was used for a midnight excursion that included getting a drink of water from my hydration reservoir hanging from a nearby tree.  I used the lamp in the blue light mode.  It was plenty bright for my chores and getting re-settled in my shelter.

Use for jogging/running

When I moved to Tucson I had to quickly adapt my running schedule -- everyone here runs/walks/bikes before the sun comes up in summer to avoid the heat of the day.  On several occasions I went out early enough (4:30 AM) that it was still pitch dark.  Tucson also has very strong light pollution rules, and many streets do not have street lights.  The K2 headlamp has come in handy for this purpose.

I have found that the white low-power beam is adequate for use while running on streets and sidewalks, even when used in the wide beam mode.  This is also the only application where I used the rear red "tail" lamp.  I found it very comforting when running on a street to know that I had a red light on to better help auto drivers to see me.

The weight of the K2 headlamp was not an issue for this application.  The split of the weight between front and rear kept the lamp from sliding down in the front when bouncing along.

Overall I have been very happy using the K2 headlamp for jogging in the dark, no complaints whatsoever.


Battery life has been excellent.  I am still using the cells supplied with the unit.

My feelings and experiences have not changed in substance since filing my Field Report.  The question I now ask myself is "will I continue to use the K2 headlamp after the test period is complete?".  My opinion is "yes, for selected trips".  I will likely leave the headlamp at home on summer trips where daylight supplies most of my needs.  The one exception might be if I head out for a trip on a Friday night after work and am likely to arrive at the trailhead at dusk.  In this case I would take the headlamp to make sure I had enough light to make my way along the initial trail section and set up camp in the dark.

I am likely to use the K2 headlamp in winter, even here in Arizona.  As the days get shorter I will be performing more activities in the dark.  I've come to appreciate the bright light this headlamp supplies, yet I can conserve battery power using the color LED lights when appropriate.  The AA battery pack is heavy, but acts as a set of backup cells for my camera and GPS which mitigates the weight penalty.

Many thanks to Essential Gear Inc. and for the opportunity to test this product.

Read more reviews of Essential Gear gear
Read more gear reviews by Kurt Papke

Reviews > Lighting > Headlamps - LED > Essential Gear K2 Focus Headlamp > Test Report by Kurt Papke

Product tested and reviewed in each Formal Test Report has been provided free of charge by the manufacturer to Upon completion of the Test Series the writer is permitted to keep the product. Owner Reviews are based on product owned by the reviewer personally unless otherwise noted.

All material on this site is the exclusive property of
BackpackGearTest software copyright David Anderson