Materials Part Material Body Cast Steel 1.0619+N Bonnet Cast Steel 1.0619+N Seat A105 and Stellite Disc Stainless steel DIN 17440 X30 Cr13 and Stellite Bellows Stainless steel DIN 17440 X6 Cr Ni Ti 1810 Stem Stainless steel AISI 420 Bonnet nut Steel ASTM A194 2H B...