The CAS 4 PelletVent Pro Combustion Air Wall Thimble Kit is a component that is used in a typical venting installation. This combustion air wall thimble kit is a direct vent for bringing outside air for combustion through an adjustable air channel in wall thimble to appliance without cutting a second hole into the wall.Kit Includes: Wall Thimble, Channel Adapter, Flex and 2 to A Direct Vent Minimizes down drafts in below-grade installations Patent-pendingADA Compliant: No Collection: PelletVent Pro Finish: Matte Black Fuel Type: Pellet Height: 14-3 4 Inner Diameter: 4 Material: Galvanized Steel Pipe Class: Class A Pipe Shape: Round Style: Contemporary Modern Weight: 3.1 Width: 9