Product Features:1. Transparent valve body design; fully transparent valve body, observe operation condition to ensure normal use2. Double-leaf replica design, upgrade clumsy single page design, two-page open fast, smoke-efficient.3. Anti-oil sticky, no leakage of smoke; silicone gasket, the use of soft washers, strong sealing effect, prevent the smell of smoke4. spring design; Check valve with spring, long use, no deformation power lasting, to ensure good sealing performance100% brand new & high qualityColor：whiteProduct Name: Flue gas exhaust pipe check valve anti-smoking POPC comprehensive performance of good thermoplastic resin, with strong compressive toughness and high temperature resistance to flame retardant properties, such as the performance of various properties than ABSMaterial: ABSsize：198x198mmPackage Contents:1x Flue Smoke controlOnly the above package content, other products are not included.Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.