Unique Bargains 2pcs N.C. Recessed Wired Security Window Door Contact Sensor Alarm Magnetic Reed Switch White RC-33

NC means Normally Closed: when the magnet is together, the circuit is conductive (light on); when the magnet separates, the circuit is not conductive (light off); Please check carefully when placing an order.

These door contact sensors are used with commercial and residential card access systems as well as security burglar alarm systems.

Works as an anti-theft alarm, perfect for metal doors and windows.

NC; means Normally Closed: When the magnet together, the circuit is conductive( light on ); when the magnet separates, the circuit is not conductive ( light off ).

The Magnetic Door Switch must be installed according to the sensing distance; It can only provide a switch signal to the transmitter; It cannot directly load the power, nor directly connect the lamp!