Worn with the fur side against skin, place these warmers inside mitts or gloves and on top of toes held snug inside socks. Using a snug wool blend sock helps to keep the warmers in place. The leather side to grip the sock when the warmer is placed on top of the toes. Be sure to remove Aurora Heat before laundering!! Body heat is stored within the fur and circulated back to the body. This passive warming system does an incredible job of holding a comfortable temperature, keeping kids warm but not overheating.