... meet customer's demand. Product Parameter ProductNylon/PA6/PA66/PEEK Single screw barrelHardness after hardening and tempering HB260 °~ Nitrided Hardness HV950°~ ... shunt type,separation type,exhaust type,pin type,mixed type,double-head type,three-head type,multi head type etc. ... ,AISI 4140 hard chrome coated layer 4Cr5MoSiV1,SKD-61,SKD-11 Sparying bimetal alloy layer and nitriding treatment HPM38,SI36, ...