This listing is for one ADF hinge, part number 302NM18021.This component is designed to fit the following printer models: M3040, M3145, M3540, M3550, M3560, M3645, M3655, M3660, M6230, M6235, M6030, M6035, M6530, M6535, and M6630.It serves as a functional replacement to restore the automatic document feeder mechanism on compatible units.