①,Material:
a)Steel, Property class (material): ≤M39：5.6,8.8,10.9; for larger sizes: subject to agreement. Standard ISO 898-1
b)Stainless steel, Property class (material): ≤M20：A2-70，A4-70; > M20 ≤M39: A2-50, A4-50; > M39: subject to agreement. Standard DIN 267-11
c)Non-ferrous metal, Property class (material): subject to agreement. Standard DIN 267-20
Note: The symbols used to denote property class as specified in ISO 898-1 and DIN 267-11 may also be used for sizes above M39 provided that the finished product has all the properties assigned to the particular symbol.