... /4”wide seal is made by a computer-controlled pneumatic heat sealer 4,Locking tie-down straps featuring SURELOC fasteners . 5,SpaLux ... industrial polyester thread . 8,Customized Perimeter skirt that helps keep heat in and dirt out ,while adding to the appearance of ... your cover . 9,Sealing ,Heat stopper pads that eliminates heat loss . 10,Galvinized steel center support that is ...