DuraVent 3PVP-60B 3" Inner Diameter - PelletVent Pro Type L Chimney Pipe - Doubl, Black PelletVent Pro is a venting system designed for stoves and inserts that use wood pellets, oil fuel, corn, and other biofuel products. DuraVent PelletVent Pro pipe features fully unitized twist-lock construction Listed at 1'' clearance to combustibles, in the USA, it can be used in both vertical and horizontal installations