APP Premium Base is a smooth-surface APP modified bitumen membrane designed to be heat-welded or installed with Elevate Multi-Purpose MB Cold Adhesive. It consists of select asphalt, modified with atactic polypropylene, and reinforced with a 1.8 lb/100 ft² (90 g/m²) non-woven glass fiber mat. The combination results in a flexible, durable, smooth-surfaced base sheet membrane. APP Premium Base is strong and stable, and resistant to natural forces and other factors on the rooftop. It is ideal for both new construction and re-roofing as a base sheet in multi-ply applications and as a base ply in flashing applications.