圆柱头螺钉用 A级垫圈,硬度最高250HV
Product Grade A, Up To Hardness 250 Hv, Primarily for Cheese Head Screws
圆柱头螺钉用 A级加硬垫圈,硬度300HV以上
Washers: Product Grade A. From Hardness 300 Hv, Primarily For Cheese Head Screws
A级小平垫,硬度200HV和300HV
Plain Washers - Small Series, Product Grade A, 200HV and 300HV