app waterproofing membrane -- Plastic modified asphalt waterproofing membrane (APP) is made of APP (Random Polypropylene) or APAO APO (Polyolefin Polymer) modified asphalt is used as the impregnation material, with high-quality polyester felt, fiberglass felt, as the base material, fine sand, mineral particles (flakes), and PE film as the covering material. It is a plastic modified asphalt waterproofing membrane refined by advanced technology.