I use this Amazon heating pad. So far from 60 hours of hanging, I’ve had absolutely no problems. It works great. Sometimes I use some extra tape even though the reusable adhesive stuff on the pad already works great. It doesn’t cover the whole shaft all the way around, but it gets most of it and keeps me warm.
“Cabric Far Infrared Heating/Thermal Adhesive Patch(Relief for Stiff Neck, Frozen Shoulder, Wrist (CTS) and Dysmenorrhea Pain)(QPU52)”