ISO: Heating Pad that I Can Wear Under My Clothes

Hey everyone, so it's that dumb week again where my cramps are hitting me on max. I was just wondering if anyone has seen, heard of, or use themselves a heating pad that like some how you can wrap around your abdomen so you can wear it under clothes. For me, the pain gets so bad that I constantly have to have heat on or else it's just unbearable. I have two heating blankets, a hot water bottle, hot towels, and a regular heating pad that I use depending on what day of the week it is.