Material：

Galvanized steel Plate (g)

Stainless steel plate (s)

Size: Custom size According to customer requirements (WXH)

Characteristics：

The blade uses the hand knob switch to rotate, may adjust any angle, to control the air volume.

The blade and the frame surface rotate the axle to have the stainless steel continuous motion piece to windproof leaks.

The large air damper is divided into compartments and reinforced.