I have a 18 ft enclosed trailer that I set upto haul four harleys in. the first two chocks I bought were the condors at $168.00 each. the second two I bought were the ones from harbor frght at $56.00 each. the only difference I can see is the ones from harbor frght has a longer/wider main frame of about 8 inches longer and 2 inches wider and the tire craddle is a little different shape. If I had it to do over I would have bought all at harbor frght! the thickness of the steel is the same. the only thing I did to them was to buy the quick disconnect from condor and used it on the harbor chocks ( with a little modification) so they could be pulled out of the trailer when I dident need them. in short the harbor frght ones are fine!