they are rivnuts with a 10mm thread....
the holes they fit into are covered in painted over tape and you have to ream them out to the exact size!
if the nut & bolt shop have the tool for setting them you'd be wise to try and borrow one.
good luck fitting them, they are a piggin nightmare
it mite help if yu change ya UserCP to show wher yu are based.
I havent tried it, but I am lead to believe that yu can fit the rivnuts by inserting a bolt and then tightening it up - that allows the nut to compress into position.
good luck
offer is there fur next week if yu want
offer is there fur next week if yu want