As a foot-warmer, it is top notch.But as other reviewers have mentioned, the product also produces an extremely pungent odor.The smell reminds me most of cat pee. I actually suspected my two frolicsome felines before I was able to conclusively track the source of the smell to the foot heater. The smell is also quite lingering.This might be a great product for a garage or an outdoor work area, but I don't think I'd recommend it for use in bedrooms or other living areas. I wouldn't mind a rubber smell, but this product does not smell like any rubber I've run across in my travels!