Uniheat Shipping Warmer 30+ Hours, 8 PACK &gt;PLUS!&lt; 1 - 10"x18" Shipping Bags, 30+ Hour Warmth for Shipping Live Corals, Small Pets, Fish, Insects, Reptiles, Etc...AND Shipping Bags to Hold in the Heat 8 Pack of Uniheat 30+ 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 Bag and Seal to Lock in the Heat and Protect from the Cold. Designed for reliable and steady heat release for 30+ hours...Excellent Heat Pack for shipping live corals, insects, reptiles, fish, flowers, etc. Provides an average warmer surface temperature of 100 degrees fahrenheit Works better than 20 Hour Heat Pack for live corals & fish because it is a more even heat with less peak temperature and the consistent heat lasts longer.