[Dimension] - Cable Length: 25cm/9.8"; Total Size: 104 x 15.2 x 14.8mm / 4.09 x 0.6 x 0.58 inch (L*W*H)
[Material] - The magnetic switch alarm is with durable zinc alloy housing for better rust resistance
[N.O./N.C.] - N.C. means Normally Closed: When the magnet together, the circuit is conductive( light on ); when the magnet separates, the circuit is not conductive ( light off ). N.O. means Normally Open: when the magnet separates, the circuit is conductive( light on ); When the magnet together, the circuit is not conductive ( light off ). When make order, pls check carefully!
[Applications] - The Rolling Door Contact is designed for use with window and door alarm systems, such as garage, industrial warehouse and shops, etc.