This "Under the Sea" pattern pack is made from double layered 100% cotton flannel as the "pillow case". The inner bag and thread are also 100% cotton. Share your blanket with the pack to heat area under blanket as well as you. Great while watching TV or reading. Also under blanket at night, Use for sore muscles, etc. Not for very young children.
Microwave for 50 seconds the first time. Then add 5-10 seconds at a time till you know the warmth you want. Almost 2 pounds.