3D Printer Extruder HFA for the 300 Series Workbench Pro3D printer extruders are mechanical devices that feed, control, and deposit filament or printing material, making them critical to print speed, accuracy, and reliability. The HFA High Flow Air Cooled extruder delivers the industrys highest performance and highest speed, which is why it comes standard on the 300 Series Workbench Pro. It features quick swap dual extruder head capability, independent control of print speed and extruded material amounts,