... range at 1.6-1.8mm/2.8-3.0mm, roundness +/-0.05mm, each spool net weight 1kg+/-0.05kgIV we put all filament ... .5.research and developing we have engineers that specialty in color formulation ,plastic modification, packaging, quality control ,producing control, we ... to your requirements . we have colors: Natural, white, black,red, sky blue, dark blue ,florescent green,dark green, florescent yellow ...