64610 Шестостенни Тежки Нутове, M = D - Нутове
High nuts, M = D (ECR HH h=d (100))
A4 stainless steel - Hh - UNI 5587
There is a variant in A2 stainless steel This high nut can be combined with a DIN 933 machine screw or a DIN 931 machine screw and a medium flat washer type M NFE 25513-25514