DuraVent Round Type B Gas Vent Model BV 4" x 5" Increaser w4 UL 441 Clearances 1" Minimum

UL 441 Clearances 1" Minimum clearance to combustibles for 3" - 24" Size 4" Pitched 6/12 to 12/12 Plate Size 20" x 20" Technical Drawings & Dimensions

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Model S20i Firebox Height 20

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DuraVent Round Type B Gas Vent Model BV 4" x 5" Increaser w4 UL 441 Clearances 1" MinimumOur non positional lock system on the Duravent BV Gas Vent is the best lock system on the market today. The incorporation of the DuraTab feature simply improves our lock system by adding flexibility and meeting market needs. The BV line of Duravent round vent pipe and fittings is designed for use on approved gas appliances in residential and light commercial and industrial applications. What's Included (1) Increaser Features Use to increase vent