Rolling Door Contact Magnetic Reed Switch Alarm with 2 Wires for N.C. Applications MC-51 3pcs Cell Phone Accessories The magnetic door latch is

The magnetic door latch is made of iron

Thread Size: G1inch DN25

2pcs x 6mm Elbow Connector

Release or tighten the bolt to adjust the band diameter range

Notice: the battery is not included here

Rolling Door Contact Magnetic Reed Switch Alarm with 2 Wires for N.C. Applications MC-51 3pcs Cell Phone Accessories The magnetic door latch isDescription: 1. Actuation Distance: 20 30mm. Silver gray zinc alloy housing. 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. NC means Normally Closed: When the magnet together, the circuit is conductive( light on ); when the magnet separate, the circuit is not conductive ( light off ).