CURT Class 3 Trailer Hitch Ball Mount, Fits 2-Inch Receiver, 7,500 lbs, 1-Inch Hole, 6-Inch Drop Model 45080 60" L This multi-ball ball mount features

This multi-ball ball mount features a 1-7/8"

but you may need this part to retrofit to an older Pro II rack or to replace on your Pro Rack

It should be noted

Buyers Products 18x18x36 Inch Pro Series Smooth Aluminum Underbody Truck Box - Double Barn Door

CURT Class 3 Trailer Hitch Ball Mount, Fits 2-Inch Receiver, 7,500 lbs, 1-Inch Hole, 6-Inch Drop Model 45080 60" L This multi-ball ball mount features*CURT Class 3 Trailer Hitch Ball Mount, Fits 2 Inch Receiver, 7,500 lbs, 1 Inch Hole, 6 Inch Drop Model 45080 CURT class 3, or standard duty, Towing Accessories are a step up from classes 1 and 2. They feature a 2" x 2" shank and have a higher weight capacity for towing heavy duty trailers, including utility trailers, boat trailers, campers, single horse livestock trailers and most recreational vehicle trailers. With class 3 trailer hitches being the