The first set lasted years, but after so much microwaving, they eventually blew up.

The casserole pan is probably 7 year and this worked great over Christmas.

The casserole pan is probably 7 year and this worked great over Christmas.

Previous one exploded took 4 years to find them these are not sold in stores.

My original hot-pack gave me many years of infrequent service until it split at the seam, probably because I might have overheated the pack.

Must take care not to overheat as it can self destruct.