PVC Plug Set for use with PVC Heating Blankets or Electric Heaters. Plug the ends of the PVC being heated, the trapped air will help keep the PVC from collapsing while forming the bend. Use on Schedule 40 and 80 PVC. 2" - 4" set includes 2 of each: 2", 2-1/2", 3" and 4" in a carrying case.