This genuine HP Size Detect Switch Assembly with part number RM2-1255-000CN is designed as a media detection component to detect the paper size within the printer path and resolve paper size errors. This genuine HP spare part is mainly used in HP LaserJet Enterprise printers and is compatible with HP LaserJet M607, M608, M609, M631, M632, and M633 models. It is a replacement-level component, recognized as SW5/SW5 size detection switch assembly, intended for accurate paper size detection in professional HP printing systems.