Description:1.Actuation Distance: 50-70mm.Aluminum Alloy Housing, Stainless Steel Pipe.2.The reed switch is an electrical switch operated by an applied magnetic field.3.Designed for use with alarm systems. Great for use in family and factory window, door. etc.4.Screw Mounted for easily install.5.NO means Normally Open: when the magnet separate, the circuit is conductive( light on );When the magnet together, the circuit is not conductive ( light off ).When make order,pls check carefully! Specification:Product Name: Magnetic Door SwitchModel: OC-60B Contact Type: NOActuation Distance: 50-70mmMax. Current: 0.5AMax. Power: 10WWorking Voltage: DC100VSize(Approx): 104 x 50 x 9.5mm, 104.5 x 20 x 16mm (L*W*H) Hole Dia.:6mmCable Length(Each): 50cm / 19.7-inchMaterial: Aluminum Alloy (Housing)Wire Type: 1007UL#22AWGColor: Silver GrayNet Weight: 217g Package Content:1 x Magnetic Door Switch, 4 x Screws