This is a Panasonic human sensor. Main unit: Beautiful condition (Opened once and installed by mistake due to incorrect model number) (No stains or dirt) Sub unit: New, unused This is a set of 4, with 2 main units and 2 sub units. Model number Main unit: WTK 24818 Model number Sub unit: WTK 29318 Automatic switch with infrared sensor 8A type wide-angle I am also considering selling them as a set of 1, so Please feel free to contact me!