A thinner Heat Ready sock made with merino wool in the foot for superior comfort. The AV30 is designed for the active user who prefers the feel of a thin sock but wants the option to add active warmth for the next level of personal comfort. It is possible thanks to the thin integrated Heat Ready panel which is compatible with the smart powerpack One from Inuheat. If you want to get the most out of your Heat Ready sock, there is also a free smartphone app from Inuheat that allows you to control the heat from your mobile, see how long the heat will last, get product information and washing advice and much more. Sock only - Inuheat One Powerpack sold separately.