SBS/APP Modified Bitumen Waterproof Membrane is a high-performance waterproofing material made of modified bitumen with added styrene-butadiene-styrene (SBS) or atactic polypropylene (APP) to improve flexibility and durability. It is ideal for waterproofing roofs, basements, foundations, and other structures exposed to harsh weather conditions. The membrane can be torch-applied, self-adhered, or cold-applied, making it versatile and easy to install.