I misplaced the anti-rattle bolt for my above-referenced bike rack, which I usually mount on a 1.25-inch receiver. The manual says the bolt is 1/2-inch by 96mm.

Curt 18085 bike rack parts list

I set out for a replacement bolt, and the part was a bit more elusive than I figured. Curt doesn’t sell the bolt by itself and it seems other manufacturers, Saris included, use a different bolt diameter. Ultimately, I ended up purchasing a replacement bolt from Rack Attack using Curt 22321, an Anti-Rattle Kit for 2-inch hitches. Even though the kit is for 2-inch hitches, the bolt that comes with the kit works with my rack.