Reverse wind protection

The leaves are made of galvanized steel and are very light and can be automatically opened and closed by the wind of exhaust, dirty air in the room is out of the building, preventing outside dust and insects from entering

Solid Spring

Shaft Action: Useful for securing duct hoses

The spring is durable and not easy to deform.

The check valve uses a hard and strong spring that can be installed horizontally or vertically.

Low Noise & Seal

A sponge strip is attached to the air vent of the damper to prevent reverse wind, which greatly reduces the noise of automatic opening and closing due to exhaust.

Sturdy damper blade and sponge strip design also improves internal sealing performance