7/16-20GR X 1.50” Chassis Bolt, this is the bolt, washer and nut combination that we prefer to use at our facility. This combination works great for multiple layer brackets for frame bracket attachment. These are Grade 8 hardware. Washers are a thick washer without the box store slip. Nut is a C steel lock nut. The bolts and washers are not coated in anything weather resistant and will need painted after installation.
