Universal pipe backdraft damper and butterfly valve designed for easy insertion into flexible exhaust hose or rigid PVC duct. Ideal for bathrooms, attics, garages, kitchens, air conditioners, inline fans, extractor hoods and general home or workshop ventilation systems. Versatile backdraft damper fits multiple duct sizes for convenient installation. Compatible with 150mm, 160mm, 170mm and 180mm hoses, eliminating the need for multiple models. Includes a 5-year warranty plus lifelong after-sales support for added peace of mind and reliable service. Automatic flap valve opens and closes with airflow to maintain efficient one-directional ventilation. Effectively prevents cold air, odors, insects and drafts from entering living spaces. Integrated inner rubber seal improves tightness while reducing Shaking and operational noise during use. Simple push-in installation allows the backdraft damper to be inserted directly into the vent pipe until fully seated. For horizontal mounting, the spring should be aligned horizontally for optimal opening and closing performance, a guideline that also applies to vertical installations for best results. Durable PVC construction ensures long service life in residential and light commercial applications. The housing and valve blades are made of robust PVC, while the shaft and spring components are also PVC-based, providing corrosion resistance, low maintenance and stable operation in humid environments. Color: As Shown Material: PP Package Contents: 1*Backdraft Damper Only the above package content, other products are not included. Note: Light reflection 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.