Uniheat Shipping Warmer 20+ Hours, 16 Pack &gt;Plus!&lt; 1-10"x18" Shipping Bags, 20+ Hour Warmth for Shipping Live Corals, Small Pets, Fish, Insects, Reptiles, Etc.and Shipping Bags to Hold in The Heat 16 Pack of Uniheat 20+ Hour Heat Packs **PLUS** 1 FREE 10"x18" Shipping Bags to Help Lock in the Heat! Simple to use Heat Pack! - Just open, unwrap, and let sit for 10+ minutes to start the heat process. Put Shipping Item in Shipping Bags and Seal to Lock in the Heat. For Extra Protection, Use Bags Double Bagged for Even Better Insulation From the Cold. Designed for reliable and steady heat release for 20+ hours...Excellent Heat Pack for shipping live corals, insects, reptiles, fish, flowers, etc. Provides an average warmer surface temperature of 70 degrees fahrenheit Maximum temperature of 110 degrees fahrenheit