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Marmot Isotherm Jacket Review

The Marmot Isotherm Jacket is one of 2017’s lesser known jackets. Trying to capatalize on Patagonia’s Nano Air success, Marmot has updated the Isotherm to be even more breathable and utilizing the Angel Wing design, it offers a better range of movement than before. They also decided the Isotherm Hoody should no longer be a hoody.

Go figure!

Marmot Isotherm Jacket

Pros

  • Excellent Warmth
  • Decent wind resistance
  • Roomy fit
  • Highly compressable
  • Lightweight

Cons

  • Less breathable than my patagonia nano air
  • A bit short in the torso
  • Hood was removed in this years model!

Feature Summary

Watch this video on YouTube.

  • 20D Pertex Quantum offering durability and some protection from light misting or snow activities
  • DriClime Mesh Lining to help wick moisture away from the body
  • Elastic Bound Cuffs to keep drafts out
  • Elastic Draw Cord Hem
  • Polartec Alpha Synthetic Insulation allowing use in highly aerobic activities
  • Soft-shell Shoulder Reinforcements for weather and pack wear durability
  • Zippered Chest Pocket
  • Zippered Hand Pockets

Warmth

Because the isotherm uses Polartec Alpha as its insulation layer its able to avoid using downproof fabrics and can opt for a pertex shell fabric which holds warmth but still offers some breathability. I found the shell fabric to be a smart choice as it also offers better rain and wind protection over the Nano Air.

Weight & Packability

The Polartec Alpha insulation, while synthetic, provides an excellent warmth to weight ratio while still compressing down to a nice size in your pack. Weighing in at 12.5oz the Isotherm manages to match the Patagonia Nano Air’s weight.

Sizing & Fit

The Isotherm fits an athletic build comfortably but is a little baggy. A stocky build would fill out this jacket much better.

Marmot Isotherm Jacket vs Patagonia Nano Air

The Nano Air is a favorite to many. With good reason. I found the Isotherm Jacket to be an on par contender with slightly different pros and cons but ultimately I will be keeping the Nano Air in rotation over the Isotherm.

Marmot Isotherm Jacket vs Rab Strata

The Rab Strata follows a similar specification list in regard to fabrics and insulation but its lack of motion enabling design lets it down compared to the Isotherm.

The Verdict

I feel the Marmot Isotherm has its place with some backpackers -- And its certainly a cheaper option over the Nano Air. Its wieght and active motion enabling design are the things I like most. Ultimately I found the Nano Air breaths a bit better and I’ll be bouncing the Isotherm.

If I didn’t already have access to the Nano Air -- I suspect my wallet would have chosen the Isotherm for me -- its much of a muchness when it really gets down to it.


Specs

Best UseMultisport
InsulatedYes
Insulation TypeSynthetic
InsulationPolartec Alpha polyester fibers
HoodNo
Back LengthHip-length
GenderMen's
Weight12.5
Shell Lining FabricPolyester
Shell Fabric86% polyester/14% spandex