... .Finish:Plain,Zinc plated 4.OEMService HEX WASHER HEAD TAPPING SCREWS 1) Differents size: M4-M122) Standard:GB,DIN,ANSI,JIS3) Finish ... ) Grade:4.8 5.8 6.8 8.8 10.9 12.95) Material:carbon steel, brass,stainless steel, spring steel ... according to customers' drawings or samples hex washer head tapping screws