Both parts print vertically, join them together with 20mm M3 bolts. The Linear bearings slide in and secure with a zip tie It has a belt adjuster on one side of the belt clamps - see photos The Extruder is based on Greg's excellent design, with a few mods and the extensions allow it to fit on the Quick-Fit X Carriage. You need two x M4 (13mm) 624 bearings for the Quick-Fit Lever. It also has a fan mount on one side.