The standard VX PIR is produced by the world leaders in PIR technology, a company called Optex. We use these PIR's as they are the best in the world and we modify them for GPRS communication.
The VX GPRS PIR is a dual optic PIR. Dual optic means that there are two seperate detection patterns, both of which must be interrupted at the same time in order to produce an activation. Essentially these PIR's when installed according to instructions, will not detect anything smaller than 1 meter tall, I.E. Dogs, cats, foxes, birds etc.
