– Material: High quality “Boron Alloyed Steel” with excellent hardenability
– We offer 60 degree metric threads with 6g tolerance after forming
– Threads are inspected by go/no go ring gauges
– All dimensions strictly comply with drawing.
– All screws are Quenched and Tempered with heat treatment furnace
– Surface hardness and core hardness is controlled in a way that ensures all the machine screws conform to property class no less than 6.8 grade. Hardness value range 350-480 HV
– White, yellow/seven color and black color Zn coating is available.
– Excellent corrosion resistance for indoor and outdoor use.
– Have 96 hours SST against red rust.
– We provide Mill Test Certificate upon request