The HP B3Q10-40079 ADF separation pad support is a document-feeder holder for selected HP LaserJet and Color LaserJet Pro MFP printers. It supports the separation pad within the feeder assembly.
The listing identifies compatibility with the HP LaserJet Pro MFP M426dw, M426fdn, M426fdw, M427dw, M427fdn and M427fdw, as well as the HP Color LaserJet Pro MFP M277dw, M277n, M377dw, M477fdn and M477fnw. The part is listed for the document-feeder section, making it a service replacement component for that assembly.