Uniheat 72-hour Heat Pack for Shipping Plants, Live Insects, Reptiles, Tropical Fish (3 Packs) Designed for reliable and steady heat release for 72+ hours. Shipping warmer are excellent for shipping live insects, reptiles, tropical fish, flowers, corals and inverts needing warmth in shipping. Produces an average temperature of 70F in a standard 1cu. ft. shipping box. Environmentally safe, disposable, and inner contents are biodegradable.