Metal step ferrule Surface :Zn Machined and turned SGS audited More than 20 years experience in special fastener 1,Name:Metal step ferrule;step ferrule;metal ferrule 2,For the similar ferrule,what can we do ?(1), Ability for the material of this kind of ferrule: Grade3.6,4.6,4.8,5.6,6.8,8.8,9.8,10.9,12.9,etcCarbon steelGr.B,Gr.C,Gr.D,Gr.36,Gr.58,1010,1015,1016,1020,1045,etcAlloy steel4130,4140, ...