K2 Spyne 120 Heat

Model Year
All-Mountain Traditional
Last Width
Flex Index
Price (MSRP)

The Gist

Not only is the 120 flex Spyne a new stiffness offering this year but the 2018 K2 Spyne 120 Heat, as its name would suggest, comes with a built-in heater! Usually on-board heaters appear on boots designed for low-end skiers, and generally give a boot a bit of a kook-allure but testers were stoked on this new cooker, and the boot!

The Fit

There was something about the new, heater-implanted LuxFit Pro Intuition liner in the Spyne 120 Heat that just felt good, testers said. They preferred its well-wrapped fit to that of the stiffer Spyne 130 LV for the 120's ideal blend of cushion, contour and firm-enough feel against the foot. The out-of-box fit was a test favorite, though we did do custom tests on this model as well and found that the fit over the top of the foot relaxed nicely (and evened the fit elsewhere, too.) A couple testers claimed that they could feel a bit of unwanted pressure at the liner's battery housing location along the lateral part of the lower leg, but most didn't notice.


The Spyne 120 Heat's performance scores (dynamic balance, edge power, quickness) beat out big brother Spyne 130's. Testers found this boot to be a well-wrought blend of comfort, balance, power and quickness—it was one of the test's best combo boots, meaning it had an evenly matched set of good qualities which made it an all-around winner in all conditions and for a lot of different skier types. Testers did not like the way this boot skied after the shell was cooked in the convection oven and "custom molded," finding it weakened on edge and unreliable afterward. Cook the liner, not the shell, was their advice.

Cool Features

The Thermic-designed heater system is slick—easy to operate, big buttons on the liner and with a nicely wrapped heat area that envelopes the whole toebox without feeling stiff or edgy. The heater option adds $150 to the list price of the non-heat 120, but considering that your typical aftermarket heater costs $250 we figure this is a bargain and a more convenient solution. GripWalk soles are available as an extra—good for strolling and for use with appropriate GripWalk bindings.

Sizes (MP) 
Hike Mode 
Heat Moldable Liner 
Boot width profile 
Also in this Collection 
Cantology Compatible 
Total Avg Score 
  • 2017-18 K2 Spyne 120 Heat at America's Best Bootfitters Boot Test
  • 2017-18 K2 Spyne 120 Heat at America's Best Bootfitters Boot Test
  • 2017-18 K2 Spyne 120 Heat at America's Best Bootfitters Boot Test
  • Kevin Gabriel testing the 2017-18 K2 Spyne 120 Heat at America's Best Bootfitters Boot Test
  • Bob Gleason testing the 2017-18 K2 Spyne 120 Heat at America's Best Bootfitters Boot Test


  • “Nice initial feel—well-contained for performance. Improved first impression.” -- Bob Gleason
  • “Quick like a gazelle in flight for its life!” -- Jack Rafferty
  • “Pretty agile and fun—it's a great boot!” -- Charlie Bradley
  • “The initial fit wasn't spectacular, but how it skied was!” -- Brian Elling
  • “Solid skiing and fit!” -- Jim Schaffner
  • “Great out-of-the-box fit and a nice flex feel.” -- Kevin Anderson
  • “Perfect scores all around—didn't want to take them off!” -- Bret Acuff
  • “Great edge to edge feel—nimble and quick in all terrain. Super slick, built-in heater!” --
  • “What happened Spyne 130 LV? The 120 Heat kicked your ass!” -- Kevin Gabriel
  • “Seriously amazing boot—at first I thought it was cheesy with the heater but it was great!” -- Dallas Goldsmith
  • “Dynamite, versatile boot. Nice and flexy without being spineless.” -- Marc Stewart
  • “Feet happy, go fast, stay planted, bend ski! Warm without burning.” -- Eino Holm
  • “Great fit and support, and my toes weren't cold.” -- Stacy Crumpler


  • “Could feel the bulk of the battery on the lateral side of calf.” -- Chris Wiberg
  • “A bucket. Seems to have no shape, just a lot of foam. I guess the heat was on. Didn't notice.” -- Jackson Hogen

This boot available at...

Seattle, WA
Telluride, CO
Telluride, CO
Pagosa Springs, CO
Taos Ski Valley, NM

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