http://massagenerd.com Soft, "frost-free" cover. Store in freezer until needed. Heat in microwave. Non-toxic, biodegradable gel. Custom printing available. Call for details.

Heating Instructions
Based on initial pack temperature below 75F (24C).

Knead after each heating. Microwave ovens vary; use care when heating and removing pack from microwave. Overheating pack may cause pack to rupture and/or leak. Carefully check the pack with the palm of your hand before applying. Discard pack if punctured or broken.

Heat 30 seconds on high heat, knead, and then continue heating at 10 second intervals until desired temperature is reached. Knead after each heating.
http://coreproducts.com