What It Says On The Box:
Important read instructions before use!!!! Over heating during shipping is more likely to be fatal than exposure to low temperatures.
These heat packs are designed for livestock shipping so no more initial over heating of livestock, followed by a rapid temperature fall towards the journey's end, as with conventional bodywarmers. They are available in either 30/40hrs+ or 60/72hrs+ hours to allow for any delays during transportation.
Suitable for personal use when travelling home with new purchases, used with confidence by commercial importers and exporters of tropical fish, reptiles, amphibians and fauna.