It just has a simple hot water bottle inside, so for the money it's not worth it at all. As soon as you fill it with water it becomes heavy for your baby's tummy so I bought it for nothing, I didn't use it.

Very cute cover, soft and comfortable. It is well insulated and after months of almost daily use, it hasn't suffered any damage! It contains a heating pad that can be easily inserted and removed, and it warms up nicely without causing discomfort or "burning" the skin. The child enjoys using it, as do I. Additionally, it cleans easily with hand washing in case it gets dirty.