U Bolt Material: Mild Steel, 45#, 40Cr,Q235 Grade: 12.9, 10. ... Size: M12~M32 Surface: Painting, Zinc painting and others U-Bolt and Nut fastenerWe are one of the top manufacturers of ... Leaf Spring, U-bolt, and Center Bolts in China:With 6 product lines and 500 workers, our ... 16949:2009 Certificate by TüV Rheinland Group German. Center Bolt for truck