The PelletVent Pro Ceiling Support Firestop Spacer is required where vent pipe passes through ceiling. The spacer centers the pipe to provide proper 1" clearance. Support Clamp is included. PelletVent Pro is a venting system designed for stoves and inserts that use wood pellets and oil fuel. It is also built to vent corn and other biofuel products (Rated for continuous use flue temperatures up to 570? F).