[Dimension] - Cable Length: 23cm/9.1"; Total Size: 49mm x 20mm x 10mm / 1.93" x 0.79" x 0.39"(L*W*H)
[Material] - The magnetic switch alarm is with durable zinc alloy housing for better rust resistance
[Normally Closed] - 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 ).
[Applications] - The Rolling Door Contact is designed for use with window and door alarm systems, such as garage, industrial warehouse and shops, etc.