Schneider Electric's Square D 9001KM1 is a 30 mm diameter transformer-style light module designed for Square D Harmony pushbutton assemblies, housing an incandescent lamp in a compact 30 mm package. It operates on 110–120 V AC and uses a screw-terminal wiring interface with a clear lens for visibility. Replacement lamp options for KM1 include GE44, with GE755 interchangeable; when ordering, prefix catalog numbers with 9001. This 30 mm light module is part of the Harmony 9001K family, providing pilot lighting for control stations and operator interfaces.
