Weekend sale! Four DANTOTSU S heaters in a set. Each heater has only two screws and round fasteners. Two of the four DANTOTSU heaters have smaller round fasteners, but they still hold in place. Please check the images. I bought these used and used them for a year connected to a thermostat. They provided warmth. These are not for individual sale, but I am also selling DANTOTSU S size heaters individually, so please take a look. Please read my profile before purchasing.