NSK uses the standard ISO clearance designations such as C2, Normal, C3, C4 and C5 for bearings with an inner ring bore diameter greater than or equal to 10mm.

• 恩斯克采用ISO标准的名称，如清除C2 ，正常，补体C3 ， C4和C5的轴承内环钻孔直径大于或等于10毫米。