... laser monitor and interlock device, smooth surface, no bumps, independent R&D, folded no break, high hardness, high strength, lots alternative ... our own patent.The quality and the production capability are guranteed.2kg/roll, 1kg/roll PLA filament 3mm/1.75mm glow-in-dark ,black,white ... 98mm,1.7-1.74mm), no bubble,high tenacity and stable melting point,which is popular in the 3D printer like RepRap, ...