These parts can be printed in either ABS or PLA, the roller may need to be adjusted in size to allow for the fitting of the bearing. For best results print at 100um (0.1mm) step height The Bearing is OD 16mm, ID 5mm, Thickness 5mm. (available through eBay) although if a 3mm ID bearing can be found this can be used and the TH spacer is then not required, although a M3 washer or two may be needed to space the roller away from the guide base. A M3 Nylon insert locking nut inserted from the rear of the Guide Base and a M3 x 20mm screw holds the Assembly together. For a pair the following are required. 2 x Guide Base 1 x Guide Roller L1 1 x Guide Roller L2 2 x TH Spacer 2 x Bearing OD16, ID5, T5. 2 x M3 Nylon insert lock Nut 2 x M3 x 20mm long Button Head Socket Screws or similar. 2 x M3 Button Head Socket screws for mounting (of appropriate length.)