Reviews > Clothing > Accessories > EZ Heat Reusable Hand Warmer > Owner Review by Adam Bowerman

Owner Review
EZ Heat Reusable Hand Warmer

Reviewer Information:
Name: Adam Bowerman
Age:22
Gender: Male
Height 5’ 10” (178 cm)
Weight: 130 lbs (59 kg)
E-mail address: adam2ant@yahoo.com
City: Atlanta
State: Georgia
Country: USA
Date: February 27, 2005

Backpacking Background: I have been hiking since I was a little kid but have only been serious about it in the past few years. During most the year I mainly do weekend trips, but during the summer months I try to do as many week-long trips as possible. I am a weight conscious hiker and try to make sure I make use of every piece of gear I carry. While hiking, I push my limits and am always trying to increase my daily distance. I hike primarily in the Southeast enjoying the variety of climates and terrain.

Product Information

Manufacturer: Prism (URL not avaliable)
Year of Manufacture: 2004
Listed weight: .5 oz (14 g)
Weight as delivered: .5 oz (14 g)
Dimensions: 4.5 x 3.25 x .5 in (11.5x8.2x1.3 cm)
Cost: $4.95 US

Material: Sodium acetate/water
Activator: Metal disc

The EZ Heat Reusable Hand warmer upon first impression struck me as brilliant. As I was shopping at R.E.I., I saw this item on the shelves and just had to inspect it. At first glance I couldn’t understand how this item worked. I saw the metal disk suspended inside the melted sodium acetate/water liquid mixture and touched the metal disk thinking that this must be the activator. I squeezed the disk from either side and nothing happened. Then I bent the disk and whala! I had just started a beautiful chain reaction that created an immense amount of heat. In less than 15 seconds the reaction had stabilized into a crystalized structure which had 15 seconds prior been a water-like liquid. My next question was how this product was reusable. I looked on the back of the package it came in and the product claimed that if I boiled the hand warmer in water for at least 6 minutes the product would return to its liquid state and would be ready to be reactivated when cooled. This was just too much for me to handle. My friend and I both decided to get one.

I went home, got water boiling, dropped the hand warmer in, and in 5 and a half minutes my hand warmer had returned to its liquid state. The hand warmer needs to be wrapped in some sort of cloth while boiling because the shell is made of plastic, which is prone to warping with contact to the bottom of the pan. The crystals also have to be completely dissolved or else the reaction will occur as soon as it starts to cool. Crystalization is really the key to these hand warmers. The bending of the metal disk gives a tiny space for the sodium acetate to seperate from its normal latice and begin to form a crystal latice which leaves you with the hot, solid crystalized sodium acetate. If the sodium acetate is not completely melted down and there are still some visiable solid white chunks, the reaction will quickly begin to occur again.

I activated the hand warmer and left it sitting on a wooden table and then collected temperatures every 15 minutes for an hour which are as follows:

Temperature after immediate activation: 127o F (53oC)
15 minutes: 120 o F (51o C)
30 minutes: 115o F (46o C)
45 minutes: 101o F (38o C)
60 minutes: 94o F (34o C)

As the measurements demonstrate, the temperature drop was fairly inconsistent. This factor can be avoided by insulating the hand warmer in say a jacket pocket or sleeping bag, but my test was to measure how long the warmer retains heat in open air.

Once I tested this product at home, and knew in confidence that it worked, I brought it with me on my next hiking trip. The plastic pouch is fairly thick, so I didn’t pack it any differently than any of my other random loose items. This weeklong trip was spent in the Natahaila National forest during fall months. The temperatures never got lower than 40o F (4o C) on this particular trip, but the hand warmer was a lovely addition even in these comfortable temperatures. I primarily used the hand warmer at night, putting it in jacket pockets, and I would then throw it in the bottom of my sleeping bag before I went to bed.

I typically boil the warmer in with the morning meal. This system is easy to do and doesn’t require me to do any extra work than I usually do. Again, as I said before, the product should be wrapped in some material so it doesn't warp on the bottom of the pot. Because of this, I must choose to either carry a material with me for this purpose or just hope to find something on the trail. I usually just put it on a stack of leaves or something in the boiling water, but I can’t assume that everyone doesn’t mind having leaf chunkies in their breakfast. My warmer has been slightly warped because I am not always careful, but the warping hasn’t caused any leaking on my particular warmer. My friend’s was left in the water too long and his did begin to leak, so beware.

I have taken the hand warmer on numerous other trips that didn’t get colder than 40o F (4 oC), but in February of this year I took the hand warmer to Pisgah National forrest where the temperatures at night were around 15o F (-9o C). In these temperatures the hand warmer really made a difference. It stayed warm for at least an hour. Keeping the hand warmer insulated adds to this time. I couldn’t keep my feet warm no matter what I did until I threw the freshly activated hand warmer into the bottom of my sleeping bag (rated to 20o F (-7o C)) and let it warm up the bottom of my bag. My feet were in heaven. It also added a noticeable warmth to my whole sleeping bag.

Things I like:
Lightweight
Cheap
Adds significant warmth and comfort
Easy to use
Things I dislike:
Having to wrap warmer in material to avoid bottom of pot
Can get too hot to comfortably have on skin

Overall: I highly recommend this product. I have had no significant problems with the product and the price can’t be beat.

Reviews > Clothing > Accessories > EZ Heat Reusable Hand Warmer > Owner Review by Adam Bowerman