TEMPERATURE COLOR CHANGE: Under 31ºC it looks Pine Green and above that it starts getting Light Orange, and when the temperature is above 45ºC, it starts getting yellow. Please note that this type of filaments should avoid long-time direct sunlight exposure. The longer the exposure time, the faster the color fade. DIMENSIONAL ACCURACY: 1.75mm filament, diameter variance of no more than 30 microns for consistent feeding and better 3D prints. SMOOTHLY PRINT: Zi-Rui engineered its Professional 3D Printer filament to strict tolerances and the highest quality standards, ensuring trouble-free operation with your 3D printer and superior results. Good shaping, no bubble, no jamming, no warping. HIGH PERFORMANCE: Orderly wrapped, melt well, feed smoothly and constantly without clogging the nozzle or extruder. Zi-Rui PLA filament is the choice of engineers, designers, and anyone else into 3D printing who demands the best. HIGH COMPATIBILITY: Perfectly compatible with most of the FDM 3D P