$18 Printrbot Simple Metal Heatbed Upgrade 3D-malli almost 2 years 1 Simple Low-Poly Pencil Holder 3D-malli almost 2 years 2 Printrbot Simple Metal extruder gantry (Designer's Placeholder) 3D-malli almost 2 years 1 PrintrBot Guide Washers 3D-malli almost 2 years 1