With long, narrow detection areas that extend from both its sides, the Optex BX-80NR Outdoor Battery-Operated PIR Detector is specifically designed to be wirelessly wall-mounted centrally on a building. The detection pattern covers the building perimeter with a multi-layered, horizontal barrier that detects intruders before they break in. Included on the unit is a backbox that accepts most manufacturers wireless systems, thereby making the BX-80NR a versatile, stable outdoor PIR requiring no wiring. To help reduce false activations, the range can be adjusted so that detection extends only to the end of the building. The unit also has a size-judging function, which helps it discriminate between large and small objects within the detection area.