3"D, PelletVent 90 Degree Elbow, Use To Offset Obstructions As Needed, Elbow Swivels 360 Degrees At Base, Angle Not Adjustable, Designed For Stoves That Burn Wood Pellets, Patent Pending Venting For Stoves & Inserts That Use Wood Pellets, UL Listed For 3" Clearance To Combustibles In USA & Canada.