Tech info    
1.Washers play a key role in keeping loose in mechanical equipment. Also known as gaskets, the market is also known as standard parts, fasteners. When a screw or nut is shaken or vibrated, such as in cars, boats and aircraft, the washer prevents it from loosening.


2.Washers are mainly divided into High tensile washers and Low carbon steel washers
The materials of 
High tensile washers: 45C,50C,50Mn, 60Mn.

Low carbon steel washers is made from scraps.

The surface coloration includes: Plain, ZP, YZP, HDG, Mechanical Zinc Plating, Black.

3.The materials of stamps parts: Q235 and Q345

The surface coloration includes: Plain, ZP, YZP, HDG, Black,Mechanical Zinc Plating,Nickel Plating