... wheel, side airproof, photoelectric switch, indicator light, buzzer alarm, control cabinet and limit switch etc spring, lead rail ... airproof, side airproof, photoelectric switch, indicator light, buzzer alarm, control cabinet and limit switch etc. LY12 aluminum alloy ... door, Rolling shutter door, Automatic door, Sliding door, Industrial sectional door, Entrance door, Perspective door, Fireproof door, ...