5/16-18 x 9 A307 Grade A Carriage Bolt Zinc Plated
I ordered the wrong size fasteners. Those were delivered quickly and exactly what I ordered. Rather than return them, I decided to keep them as I will need them in the future. I ordered more but the correct length this time. Again, received order quickly and puoduct was exactly what I ordered and expected. But, this th ime they fit. Awesome.