Its a double axle, don't have the exact measurements offhand, but its wide and pretty long. It works but its beat up. Since this picture was taken the fenders were taken off and I dont have the ramps anymore. I think its a 2 5/16 ball.
Ok sorry Ill have to pass. My jimmy is just big enough to pull a car on a trailer but w/o elec brakes it would be a death sentence to try to stop. Good luck with the sale it will go quick. Good Price.