some seat post lugs are half threaded, to use a common bolt, some are made to use a special bike seatpost binder bolt ..

Of Course, specific, OP didn't say.. Is the binder bolt part of a separate band, or integrated?

NB: there have been thin 5mm and thick 8 mm seat post QR 'skewers' .



I had to cure a Brompton seat post slipping, I've written about that before..


good luck.





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