OPC drum cleaning unit compatible with FS 6025, FS 6030, FS 6525, FS 6530, FS 305, FS 3040, FS 3050, FS 3060, FS 3550, FS 180, FS 181, FS 220, FS 221, and FS 1648 printers.Each unit is tested to meet functional specifications for drum cleaning as intended by the design.