VEXEN electric sensor HF-360-15KW comes from WAVO group.It emits and bounces high-frequency 5.8GHz electromagnetic waves. It detects through wood, plasterboard panels, glass and plastics. The sensor is so small You can hardly see it. But it sees everything. Sensor can be installed in a lighting fixture and combination of built-in twilight sensor and time relay create super energy efficient solution! VEXEN electric HF-360-15KW high frequency sensor have 3 years warranty.