Thank you.
Begging pardon, are you confident as to M13 13mm ?
My main fixing bolts appear to be 14mm and that typically corresponds to a 22mm hex head. And M13 appears to be a slightly uncommon size? Your fixings are USA supplied, are they definitely metric?
I'm going to visit my local tools and fixings trade counter. My towbar is fitted/fixed fine OK but I want to sort this "detail" ...
Stephen
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