FB seat belt bolt size or seat belt tongue size
 

Looking for some option for making the seat belt longer so it will fit right. Do not want to go to racing harness set-up. Any suggestions.

seat belt bolts are an SAE standard size, so every car in the world uses the same thread

International seat belt bolt standard is 7/16 NF (7/16-20).

I don't know how this will help, though.

That answers why a metric wrench wasn't quite right. I kinda figured they might have standardized it.

Thanks

since the SAE standard is only the thread, the later Mazda's have a metric head on the bolt.

Mazda usually only sells the bolt with the seatbelt or buckle, so not a lot of part numbers, although they do vary in length

They really don't want you using any random bolt for the seatbelt!

7/16-NF is a weird size even in SAE even though it is a "standard" size. Sort of like how a lot of engines' head bolts are 9mm or 11mm thread.

When you relocate a battery to one of the storage bins, it helps to use a seatbelt bolt to ground the battery to a rear seatbelt "bung". Clean the paint off the metal and it works great. Thoughts?