The PolarFit ultra-fine-grinding mill is available in a range of sizes to meet your needs Model 100 200 400 800 1200 1600 Scale-up factor 0.25 1.0 2.5 6 8.8 13 Median rotor diameter in 4 8 16 32 48 64 mm 100 200 400 800 1200 1600 Speed rpm 22,000 12,000 6,000 3,000 2,000 1,500 ...