49x1179 Fuser Unit For MS421dn MS421 MS 421 421dn Fuser Assembly Replacement fuser unit designed for use with specified printer models.This assembly is engineered to provide consistent performance and during print cycles.The unit integrates key components necessary for the fusing process, toner is properly bonded to paper.Built for , it supports standard print volumes and is compatible with the designated device series.Installation is straightforward, following standard procedures for fuser replacement in the supported models.