Open Source Filament: the first XYZ 3D printer that allows 3rd party 1.75mm ABS and PLA filaments New Aluminum Print Bed: more even heat distribution compared to common glass print bed allows a higher level of prints and New Innovative Calibration System: newly designed, frustration-free sensors and knobs ensure each print is perfectly calibrated UL listed “for the purpose of classification or evaluation with respect to one or more of the following: (1) specific risks only, e.g., casualty, fire or shock, (2) performance under specified conditions, (3) regulatory codes, (4) other standards, including international standards, or (5) such other conditions as UL may consider desirable.