Heat Factory Foot Warmer Insole
This is a great way to give your feet a little extra warmth on those cold days in the field. Foot warmer insoles are thin, air-activated warmers that are designed to fit in almost any shoe or boot. They will provide you with up to 6 hours of soothing gentle warmth beneath your feet. Air activated, non-toxic and odorless. No trimming necessary. Approximately 8 inches in length.