Positive SSL
1 (1)GC (2)C (3)CBN (4)D (5)A (6)WA,上列砂輪之磨料,硬度由高而低依序排列
A (1)(2)(3)(4)(5)(6)
B (1)(3)(2)(4)(6)(5)
C (4)(5)(3)(1)(6)(2)
D (4)(3)(1)(2)(6)(5)