One of my non-negotiables on the trail is the ability to have a warm beverage. Sometimes it is to take the chill off.  Sometimes it is to provide nourishment. Sometimes it is just to provide the comfort that exists in being able to conjure up fire and warmth when Mother Nature is so often the one in control out in the wilds.

GSI outdoors infinity backpacker mug_1

To that end, I have tried plastic double wall mugs, steel double wall mugs and even small, sealable carafes (foolhardy whim) as preservers of heated fluid. What I had not tried was a single wall plastic option with an insulating wrap (cozee) like the GSI Outdoors Infinity Backpacker Mug. It is ridiculously lighter than any of my other options at 3.42 ounces (versus 12.1 ounces for a double wall stainless option) and the flexible woven handle is both effective and convenient as you can hook it to almost anything and it folds down for storability. It is compact at 4.6 inches by 3.6 inches and withstood a beating by being dropped and banging around on the back of my pack. Initially, I was concerned with the lid. Due to its squat appearance, the lid is very wide, which at first glance gives the impression that there is a lot of surface area to leak as well as create pressure when upside down and full of liquid. When filled and turned upside down, however, there was no leakage from the spout or the seal of the lid. The poly insert then slides out of the sleeve for easy cleaning.

GSI outdoors infinity backpacker mug_2

The trade off for all of this ease-of-use and portability goodness? Much more rapid temperature loss. Whereas a stainless double wall mug with the same capacity will only lose 4-6 degrees per hour, the GSI lost 15-20 per hour, so it is not a “boil water in the morning and make soup at lunchtime” option but I will take the positive gains in carry weight and flexibility in packing over the net temperature losses for almost any 3-season trip.


  • No weight penalty
  • Ease of packing or hanging on outside of pack without banging around
  • Easy to clean
  • Strong, leak proof seal on lid and on sip opening seal
  • BPA free

GSI outdoors infinity backpacker mug_3


  • Far more rapid heat loss than other options on the market
  • Cozee can catch on briars and tree limbs if hung on outside of pack

Manufacturer: GSI Outdoors

Date available: Currently Available

Manufacturer’s Website:

MSRP: $9.95

Listed Weight: 3.5 oz

Actual Weight: 3.42 oz

Materials: polypropylene inner/ foam sleeve

Notes: BPA free

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