The hardened steel extruder gear assembly is an internal component of the hardened steel extruder unit. It comprises a driven gear and an active gear that work together to feed filament into the hotend. Built with heavy-duty materials, the extruder gear assembly is designed for long-lasting performance. However, if abrasion or clogging occurs due to extended use, the extruder gear assembly can be easily replaced. Thanks to its hardened steel gears, the extruder unit is capable of printing with tough engineering filaments like carbon fiber nylon and glass fiber nylon. *the P1P stainless steel extruder can be upgraded to a hardened steel extruder by just replacing the extruder gear assembly.