K0 K1 K2 K3 K4 K5 K6
Extra Fine 28~40 15~50 28~40 15~50
Fine 40~60 50~60 50~60 40~60 30~60
Medium-Fine 60~80 60~90 60~80 60~90
Medium 80~100 80~120 90~120 80~100 90~120
Coarse 140 150 140 150