he's talking about on the seat.
the cover on the back has those two big screws
when you take off the cover, you're supposed to put the screws back on, but with large plastic washers
if you don't use the washers, there's an odd space because the screws don't go all the way in by design (to avoid cracking the seat cover i think)
and can get caught on passengers gear tearing the cover mounts.
if you leave the scews off, the cover mounts look like doodoo and can get snagged as well.
the washers have a bevel to them to avoid snagging.
when i got my bike.. the dealer (AMS) had used the washers on the stock mirrors as washers for mounting
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destroying them.
I have yet to replace them, but i only run solo seat with cover all the time now.