Heats up, but doesn’t fit over entire head [SEP] I was looking for a cap to use while I was using an at home Malibu crystal gel treatment. Pro - It’s very easy to use. Con -  the heat doesn’t evenly distribute. It is only hot in the back, not anywhere around the bottom of my head or the top front of my head). Also, the cap is pretty small and doesn’t fit over my whole head. I also have short neck length hair, so my hair taking up space isn’t an issue. This is the biggest issue with it. But if you’re interested in just heating the back it would work. I wouldn’t recommend it if you have long hair.