Arrowbase is non-porous base sheets, uniquely designed and constructed to be simultaneously strong and wrinkle resistant. This unique combination of strength and suppleness is achieved by coating a heavyweight, specially designed fiberglass mat with Type IV asphalt. The asphalt coating helps maintain a uniform consistency on both sides of the sheet and eliminates pinholes. Arrowbase is used as the base ply in a wide variety of hot, cold and torch-applied built-up and modified bitumen roofing applications. The suppleness and extreme pliability of Arrowbase makes it a good alternative for organic base where a decay resistant inorganic mat is desired.