Free
It's free to download
Technical
-2x 16mm M3 screws
-1x 20mm M3 screw
-1x 624UU bearing
-1x 16mm M4 screw + nut
-1x 15mm long 8mm diameter strong spring (Ikea clothespin is perfect)
-1x Extrusion Head Gear Inner Hole Diameter 5MM and 11mm outer diameter
-1x Nema17 stepper motor
Free