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Reviews > Snow Gear > Snowshoes > Tubbs NRG Flex Snowshoes > Test Report by Michael Williams


INITIAL REPORT - December 18, 2009
FIELD REPORT - March 02, 2010
LONG TERM REPORT - April 30, 2010


NAME: Mike Williams
EMAIL: mlebwillATyahooDOTcom
AGE: 36
LOCATION: Milliken, Colorado, United States
HEIGHT: 5' 9" (1.75 m)
WEIGHT: 225 lb (102.00 kg)

I was introduced to backpacking as a teenager through scouts in Colorado Springs, Colorado and fell in love with it. I continued to actively backpack through college and took a break to start a career and family. A few years ago we decided as a family to become very active in hiking, backpacking and camping. Currently my wife, son (8 yrs) and I hike and backpack extensively in Colorado and South Dakota as a family. We continually look for the right balance of lightweight, durable, comfortable and safe gear for our family to enhance our outdoor experiences.


Product Information

Flex NRG

Manufacturer: Tubbs Snowshoes
Year of Manufacture: 2009
Manufacturer's Website:
Model: Flex NRG 24
MSRP: US$ 179.95
Listed Weight per pair: 4.2 lb (1.9 kg)
Measured Weight per pair: 4.2 lb (1.9 kg)
Listed Dimensions: 8" x 24" (20 x 61 cm)
Measured Dimensions: 8" x 24" (20 x 61 cm)

Optimal Load: One Size packed or variable snow and 190 lb (86 kg) recommended load in powder conditions

Warranty: Limited Three Year Warranty

Product Details

The Tubbs Flex NRG 24 Snowshoes (henceforth referred to as Flex NRG or snowshoes) are a composite molded hiking snowshoe. The Flex NRG are the hiking snowshoe model in Tubbs's new Flex line of compact molded snowshoes. The Flex line includes the Flex ALP for mountaineering / backcountry activities as well as the Flex TRK for trail walking.

The primary features of these snowshoes are the FLEX Tail, Composite Molded Torsion Deck, 180FLEX Binding System, 3D Curved Traction Rails and the Soft Strike Zone. Each of these features were included with the long distance hiker in mind focusing on minimizing joint stress through impact absorption as well as lightweight features to reduce fatigue. Additionally, Tubbs claims that the combination of features reduce noise and "the only thing you're listening to is the wind in the trees".

Initial Impressions

These shoes are a significant improvement in technology when compared to the tube aluminum frame snowshoes I have used in the past. They look to be more compact, lightweight and less bulky than my old clunky, big and heavy shoes. Additionally, the traction features are the most noticeable differences from what I am used to using.

Lateral Traction Rails

Most snowshoes I am familiar with include a pivoting toe crampon that provides forward traction, the Flex NRG includes this feature but also includes side lateral traction bars was well as snow breaks that are incorporated into the composite molded deck. The toe crampon as well as the lateral rails are made from powder coated carbon steel and appear to be very durable. The lateral rails are riveted to the composite deck and the toe crampon is riveted to the binding system.

Snow Breaks

The binding system is attached to the lateral rails with aluminum pins that allow for the pivoting action with each step. The 180FLEX binding system is modeled after Tubbs's patented 180 binding but lighter and with "step in convenience". It is a very robust looking binding system that essentially wraps the foot with control wings that also helps stabilize the heel. It appears that the 180FLEX binding will securely fasten a boot to the snowshoe while minimizing pressure points.

With Boot

The decking of the snowshoe comprises of the composite molded outer frame and tail as well as the Soft Strike Zone that is located where a boot heel will impact the snowshoe when walking. The composite frame and decking are made from a two-toned gray material that has the Tubbs logo as well as the Flex NRG branding prominently displayed.

Binding in Pivot

The material is fairly rigid and works in conjunction with the lateral rails to form the primary support system of the shoe. The Soft Strike Zone is comprised of a softer / pliable material that looks like it will disperse and absorb the impact of a heel strike quite well. As previously mentioned, snow breaks are incorporated with the composite decking but an additional snow break is riveted to the Soft Strike Zone as well.

Trying it out

While I have not had an opportunity to use these shoes in the backcountry I have slipped them on and experimented with the bindings. At the time of this review the Tubbs website offered a video instruction on how to "step into" the 180FLEX binding system. The video is very basic, but it illustrated how easy the binding is to engage and disengage.

Front View

I have not used the shoes to any extent, the binding did not appear to cause any pressure points or feel uncomfortable while pivoting. At this point I think the binding is very impressive and I am very eager to try these out in the snow. They are very easy to use without gloves or cold hands and it looks like I will be able to secure the bindings with one hand. However, my initial reaction to the trimmed down version of the binding is that the straps look thin and it may be difficult to fasten with cold or gloved hands.

Testing Strategy

I intend to use these shoes primarily on packed or frequently used trails for day trips in Northern Colorado during this test series. We have planned an overnight yurt / hut trip, however given the load restrictions for deep powder conditions I may not be able to use these shoes for that trip. I plan on focusing my testing on (but not limited to) the following aspects of these shoes within the two month Field Report phase.

  • How comfortable are these shoes?

  • Does the binding securely fasten boots to the shoes?

  • Are they durable?

  • How does cold temperatures affect the composite material and binding system?

  • How well do the traction features work?

  • Since I am over the recommended load limit for powder, how much flotation do these shoes offer?

  • Will snow and ice "cake" the carbon steel or composite decking material?


I am excited to test these snowshoes as they are a significant change in design from what I am used to. There are a few points that I will be cautious with when testing such as the durability of the aluminum pins that secure the binding to the snowshoe. The lateral rails and traction features are very intriguing as is the binding system and I intend to put them to good use.

This concludes my Initial Report. The Field Report which provides more details to my experiences durring a two month period with this product can be found below. My thanks to and Tubbs Snowshoes for allowing me the opportunity to test the Flex NRG 24 Snowshoes.


Field Conditions & Performance

During the Field Report phase of this test I have used the Flex NRG snowshoes on 8 day trips in Colorado, nearly all in Rocky Mountain National Park for approximately 50 miles (81 km) of use. The conditions that I used the shoes ranged from 10 F (-12 C) to 40 F (4 C) and in blizzard to sunny conditions. I have taken these snows off trail in very deep powder and used them on broken and packed trails in areas that had around 30 in (76 cm) to 60 in (152 cm) of snow pack. Additionally I have used them for some fairly steep ascents and inclines.

At this point I would like to note a disclaimer that I am over the suggested loaded weight of 190 lb (86 kg) without a pack. After adding the weight of a 15 lb (7 kg) pack, I am approximately 50 lb (23 kg) over the suggested load without factoring the additional weight of winter clothing. While acknowledging that there are conditions that I should not use these shoes I have been very pleased with the performance of the Flex NRG snowshoes.

My initial impressions of the shoes indicated that I was very impressed with the binding system and I am impressed but I have mixed feelings towards them. To begin, they are very easy to fasten with or without gloves. They are sturdy, easy to secure and have never loosened or disengaged spontaneously even with caked on snow and ice. The control wings of the binding system do a superb job of securing my boot (a standard non insulated Gore-Tex hiker with thick wool socks) to the shoes without slippage or pressure points. There were two instances where I noticed the bindings and they felt uncomfortable; first when my boot laces loosened and when I performed a kick step on a steep incline. With the kick step I noticed that my boot shifted forward on impact and I felt pinching of the control wing and they did a great job restraining my boot from coming out of the snowshoe.

The only issue that I have with the binding is how robust they are, which is normally a good thing and why I have mixed feelings about them. I feel that they are almost like a snowboard binding and the control wings secure the boot so well that it is almost like an ankle support. The binding is so strong that when the deck of the snowshoe rolls from side to side my ankle went with it. Generally this has not been an issue; however, I was on a fairly steep trail and I mis-stepped, the shoes rolled and I nearly sprained my ankle. I should have been paying more attention, then again I have done that in the past with more forgiving binding systems that allowed more room for error. Additionally, due to the robust nature of the bindings, it is incredibly difficult to lash the Flex NRG shoes to a backpack when not needed; I ended up carrying them by hand instead of having them on my pack like other snowshoes with a lower profile binding. Having said that, those same binding systems that are more forgiving and packable did not perform as well in many areas such as kick stepping, so it is a trade-off that should be considered.

I would say that the composite decking performs as advertised and is solid, fairly quiet. The flexible tail drags nicely on the snow and I experienced very little kickback of snow from the tails. I do believe that the flotation of the tails reduced the amount of snow that I would have to pull out of with each step making it easier for me to walk and therefore conserving energy. I am indifferent to the "Soft Strike" landing zone and noticed no impact benefits, but I didn't notice an issue either. The only time that I did notice the landing zone was on the decent of my longest and coldest trip, I heard a high pitched squeak with each step from my right shoe.

On a packed trail

Before I share any input on the flotation of the shoes I would like to re-reference the disclaimer I have made of my weight versus the suggested load weight. I have taken these shoes on unbroken trails in deep powder, they do adequate, however I have frequently sank to my waist in pure powder in these shoes because of my excess weight. Because of that I prefer and tend to stay on broken or packed trails that have less than 20 in (51 cm) of powder with these shoes. In preferred conditions I love these shoes; they do offer a certain level of flotation even for me.

Sinking 10" (25 cm) in fresh powder

The greatest benefit and area that I am most impressed with is the traction abilities of these shoes. While using these shoes I have never slid or slipped even though I have assented some very steep terrain with them. They work great on packed powder or ice and the best way I can describe them is that they bite into whatever is under them. The side traction rails were great while traversing an incline by offering a solid footing with each step and adding superb stability. Herringbone steps were also areas that the traction bars excelled on; caution should be used with this step as the bars can be dragged over the tail of the opposite shoe and the traction bars can act as a saw to the composite decking. The toe crampons work as well as any I have ever used. They bite into snow and ice and make steep vertical assents quite easy. I have noticed that the coatings on the toe crampons as well as the traction bars are showing signs of wear, nothing abnormal given the conditions I have used them in, but it is present.

Damage to decking from traction bars


I have tested these shoes in a wide range of conditions, from below freezing blizzards to sunny warm days with slushy snow and believe that I have used them enough to form an opinion. Knowing that I exceed the weight recommendations I am comfortable commenting on the following items.

Things I Like…

  • They excel on packed and broken trails

  • The traction devices are superb

  • Constructed with durable and quality components

  • The binding system has not failed or spontaneously disengaged

  • They are very comfortable and a pleasure to use

  • I do believe the design maximizes energy efficiency

Things That I Would Change…

  • I'm torn over the binding - I wish the shoes were more compact and packed better

  • The traction devices are so good they will bite into anything that gets in their way, including branches or saplings that could be a tripping hazard

  • When the control wings are frozen the shoes are a bit hard to step out of - special care should be taken


Overall I like these shoes; they are well made and smartly designed. Since I am over the recommended weight these shoes will be limited to broken and packed trails with the occasional off trail adventure if conditions are good. I will continue to test the Tubbs Flex NRG snowshoes and will be surprised if I return with differing results. Over the next two months I plan more day trips in addition to a weekend overnight trip however spring is around the corner and I should be able to experience more wet and dense snow.

This concludes my Field Report of the Tubbs Flex NRG 24 Snowshoes; my Long Term report has been amended below and includes the details of the continued use of the shoes.


Field Conditions and Performance

Since the Field Report I have taken the Tubbs Flex NRG snowshoes out on three trips to the mountains of Northern Colorado. This consisted of 2 day trips to Rocky Mountain National Park, both trips were on "blue bird" days and the weather was perfect. These trips both occurred directly after snowstorms that left over 10" (25 cm) of fresh spring snow and we took the opportunity for some backcountry off trail adventuring. I was very pleased with the performance of the shoes in the new snow, I did not experience any flotation issues and traction was superb.

Enjoying fresh sturdy snow.

On the final trip of the season we took the Tubbs on a multi night trip in the Colorado State Forest. This trip occurred during the spring thaw and the afternoon temperatures reached 50 F (10 C) and the snow was less than ideal. The snow conditions during this trip consisted of a layer of hard, windblown ice with a very sandy and unstructured slush underneath. With the addition of a 40 lb (18 kg) pack I regularly broke through the hard top layer of snow and sank, flotation was a considerable issue during this trip.

Battling old, crusty weak snow.

These trips were both enjoyable but certainly impacted by the quality and type of snow that I encountered. I believe that both of these examples highlight the findings in the Field Report that these shoes perform well in sturdy and supportive snow and are limiting to me in less supportive powdery snow.

A squeak was mentioned in the Field Report coming from the landing zone of the "Soft Strike" feature. This issue persisted and has become more frequent throughout the Long Term phase of testing. The shoes do not show any signs of abnormal wear or damage in the area that the noise is originating in; however I am wondering if the "Soft Strike" material is weakening from continued use.

Final Conclusion

I believe that I tested the Tubbs Flex NRG snowshoes fairly and under numerous conditions that will allow me to form an opinion of them. I have found the Tubbs Flex NRG snowshoes to be very enjoyable as they performed well in the conditions that they were designed for. Those conditions include groomed, packed and icy trails and I feel that the shoes are exceptional in those arenas.

I find the binding to be large, bulky and awkward to pack but they are also very sturdy, comfortable and easy to use. The traction devices on these shoes are by far the best that I have ever used and leave no room for improvement; however care should be taken as once the powder coating is removed or chipped off I have seen small signs of rust and corrosion. The composite material is very durable and tough and can withstand the harshest conditions while maintaining a relatively flexible action that allows for a natural gait.

Overall these shoes performed well through solid construction of durable materials that have been assembled in a smart and innovative design and they are my new standard in snowshoes. I really enjoyed testing these shoes and look forward to years of continued use from them. My thanks to and Tubbs Snowshoes for allowing me the opportunity to test the NRG Flex snowshoes.

This report was created with the Report Writer Version 1.5 Copyright 2010. All rights reserved.

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