I have found that kicking my heating materials off the bed is a sure fire way of turning them off without the trouble of looking for a switch, or having to unplug them. Ditto for the kind that turn off automatically after a set period of time. Doing so does not permit me the space and air I require in a quick enough manner. At present, I have not found any heating materials that I want near my person for an exceedingly long or personal period of time. Still searching.
