The Adrenaline Pro S1K GTX BOAA(R) Boot is a mountain-focused boot for the most aggressive riders looking for premium warmth, support and comfort. Featuring a new custom-developed MichelinA(R) sole for grip and durability, the Adrenaline Pro S1K GTX BOA Boot is modeled after the Adrenaline Pro S GTX BOA Boot, the most popular boot in snowmobiling, and delivers the same high-level performance now with the additional warmth of 1,000G 3M(TM) Thinsulate(TM) and superior comfort of the OrthoLiteA(R) O-Therm(TM) aerogel insole technology, a molded tongue for better support on the running boards as well as stronger BOA dials designed to pop off and reattach rather than break off for longer-lasting adventures. GORE-TEXA(R) GUARANTEED TO KEEP YOU DRY(TM) 3M(TM) Thinsulate(TM) Insulation - 1,000G MichelinA(R) rubber outsole for grip & durability BOAA(R) H4 coiler system & durable BOA SS2 lace Open lacing system sheds ice and debris Molded tongue & sequence lacing distributes closure force evenly Durable midsole with walking comfort Removable aerogel OrthoLiteA(R) O-Therm(TM) insole Breathable, moisture-wicking liner Half-size insert for adjustable fit D-ring for pant leg retention Entry assist pull tab Women&';s sizing: size down 2 from men&';s Women typically select 2 sizes down.