USA | European (Grade) | Micron Size | Surface Finish on Stainless Steel | |
RA µm | RA µ inch | |||
60 | 60 | 250 | 2 | 85 |
80 | 80 | 180 | 1.65 | 70 |
100 | 100 | 150 | ||
120 | 120 | 106 | 1.50 | 50 |
150 | 150 | 90 | 0.75 | 30 |
180 | 180 | 75 | 0.62 | 25 |
220 | 220 | 68 | ||
240 | P280 | 52 | 0.45 | 18 |
280 | P360 | 42 | 0.40 | 15 |
320 | P400 | 34 | 0.25 | 10 |
400 | P800 | 22 | ||
600 | P1200 | 14 | ||
800 | P2400 | 8 | ||
1000 | P4000 | 5 |