Our company was founded in 2007. After more than ten years of continuous market development, the enterprise strives to improve product quality. Gradually expand the scale from 4 nut machines in 2007 to 5 nut machines and 5 bolt machines today. Now specializing in the production of 12.9 grade internal and external bolts din912.gb5872.5783. Material 35crmo.42crmo is used to produce grade 12.9 bolts. Nut specifications include GB / t6170, GB / t6175, sh3404 and a194-2h. If necessary, please contact us.