The FAMCO BVDS exhaust vent is made of High Density Polyethylene (HDP). HDP is one of the most versatile and widely used plastics available. Outdoor integrity is maintained in all of our plastic products by the addition of UV inhibiters which protect the material from deterioration in sunlight. The stem on the BVDS can be removed if not needed for hard connect applications and the screen can be removed, to be used as a roof mounted dryer vent. The BVDS is available in black, dark brown, brown, gray, wood gray, and white. This comes in two different sizes to connect to a 4" or 6" duct - exhaust line.