Take my advice and buy one from Hensley. Mine is 10" and 1/8" thick NOT 1/4". With the thick jaws of the B&W it is much easier to see when you have taken the load off the hitch with the 1/8" disk. If the disk does not fit tight lay it on concrete and tap the inner circle of the plate with a hammer and it will tighten right up.
I bought two incase someone takes mine or something happens to one.
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