Schneider Electric Harmony 9001B11 is a black 30 mm selector switch knob (round shaft) designed for non-illuminated Harmony switches, compatible with 9001K and 9001SK models. It functions as a replacement knob for 30 mm diameter switches in control panels and machines, allowing straightforward manual actuation on a round-shaft shaft. Common applications include industrial machine controls and panel assemblies where a durable, standard black knob is used to indicate the selector position on 30 mm Schneider Electric Square D hardware.
