I thought I would show off my new shiny balls. I recently acquired a small 4x8 trailer with a 1 7/8" coupler and rather than buy a 2nd hitch and ball, I found this setup. Picked it up a Academy for about $40. It comes with a 1 7/8", 2", and 2 5/16" balls and is rated at 8k lbs. If you don't need the 2 5/16" then they have a kit with only the 1 7/8" and 2" for $5 less, but I went ahead and got the one with all 3 in case I ever needed it. I looked a a couple of other brands but wasn't very impressed with the locking mechanism and from what I read, you couldn't leave the ball on the shank unless you had a trailer hooked up. The release mechanism on this one is very easy to operate and it's impossible for it to fail with a trailer on the ball. Also, the ball is able to spin on the ball bearings so the trailer coupler isn't constantly grinding into the ball.
My new shiny balls
I recently acquired a small 4x8 trailer with a 1 7/8" coupler and rather than buy a 2nd hitch and ball, I found this setup. Picked it up a Academy for about $40. It comes with a 1 7/8", 2", and 2 5/16" balls and is rated at 8k lbs. If you don't need the 2 5/16" then they have a kit with only the 1 7/8" and 2" for $5 less, but I went ahead and got the one with all 3 in case I ever needed it. I looked a a couple of other brands but wasn't very impressed with the locking mechanism and from what I read, you couldn't leave the ball on the shank unless you had a trailer hooked up. The release mechanism on this one is very easy to operate and it's impossible for it to fail with a trailer on the ball. Also, the ball is able to spin on the ball bearings so the trailer coupler isn't constantly grinding into the ball. 
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