Grabber® MyCoal™ Heat Treat Foot Warmer Insoles The Grabber Heat Treat foot warmer insoles fit in your shoe or boot to provide you with over 5 hours of soothing warmth beneath your feet. Simply open the package and the Warmer begins to heat up instantly when exposed to the open air. They also help to eliminate sweat and natural foot odor and are non-toxic and biodegradable. Display Box of 30 packs.    Size: Sm-Med or Med-Lg Suggested Retail $4.50 per pack