These heat packs offer a unique opportunity to get the message across. With a snap of the activator disc the user will both see the liquid content crystallise and feel the product heat up to over 50 degrees in under 30 seconds. What better way to make a lasting impression? The heat packs are placed in simmering water for 10-12 minutes to return them to the original state, ready to use again, a process which can be repeated hundreds of times. Comes in clear or white phthalate free PVC. Also available in oval, square and heart shapes.