These carriage bolts are made of high quality 304 stainless steel, high hardness, corrosion resistance, anti-rust, beautiful and practical, suitable for indoor and outdoor. They never rust even in the damp environment with high ability of oxidation resistance.

Package List:
10pcs Carriage Bolts: Thread size 5/16-18 inches, screw length 1-1/2 inches (38.1mm);
10pcs Compatible Hex Nuts: Thread size 5/16-18 inches, thickness 5.56mm, across flats dimension 11.11mm;
10pcs Flat Washer Special for 5/16" Blots: Size 9x17.8x1.6mm

These above carriage bolts, hex nuts and flat washers are all made of stainless steel, produced with the same standard, could be tightened well, easy to fix and install.