The Printrbot Simple with Heated Bed (Model 1403) fully assembled 3D fused-filament-fabrication printer has a black powder-coated all-metal construction with open platform for fabricating parts up to 6 x 6 x 6 inches (H x W x D) using 1.75-mm PLA/ABS thermoplastic filament (sold separately). The frame is made from steel and aluminum for durability, and it has a black powder-coated finish to protect against wear. The printer head moves on the Y (backward and forward) and Z (up and down) axes, while the print bed moves on the x (left to right) axis. The Mic 6 machined aluminum heated print bed is warp resistant and includes an auto-leveling probe that works with the user-chosen computer software to provide a level print surface. The hot end has a maximum resolution of 100 microns and includes a fan to help solidify the molten filament as it is extruded onto the print bed. The printer uses open source software and connects to the computer using the included mini-USB cable. Using an SD card (sold separately), the printer can be disconnected from the computer after initialization for untethered printing during long print jobs. The guide rails have a 12-mm diameter for stability and have linear bearings for smooth vertical movement of the print head. The GT2 belt and aluminum pulley system facilitates precise movement of the print head. The NEMA 17 stepper motor meets the National Electrical Manufacturers Association (NEMA) standard ICS 16-2001. The printer includes a sample spool of PLA (polylactic acid) filament.