The WINGUARD infrared mini-barriers are unobtrusive multiinfrared transmitter/receiver units housed in robust aluminium housings, which are one and two metres high respectively. With their 6 metre range, they are ideal for outdoor perimeter protection of windows and doors. The small dimensions of the the Tx and Rx units (only 23mm wide), makes them suitable for installation just on the outside of windows and doors. Both transmitter and receiver are supplied with approximately 2 metre screen cable to simplify installation. Winguard are fitted with 4 twin active infrared beams, Which are syncronized and controlled by a microprocessor. The alarm is activated when one of the beams is obscurated by an object with at least a 10mm diameter for a duration of 90 milliseconds.