Trailer Hitch Ball Mount
 

I could have used this bit of information prior to ordering my trailer hitch from etrailer.com. That way I could have ordered a trailer ball mount from them at the time.

The inside top surface of the receiver tube on a Curt 13130 class III trailer hitch with 2 inch receiver tube when mounted on a RDX is 13 inches above ground.

For a trailer coupling that is 17.5 inches from the ground to the lower edge, a trailer ball mount with a rise of roughly 4.5 inches would be required for the trailer to be level.

Recommended dimension to clear bumper: minimum 9.5 inches center of hitch pin hole to center of ball hole when used in the "Rise" configuration.

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