Anyone know where I can find these? They hold the two halves of the Bose enclosures together and my car is missing a bunch. The screw is about 4.2mm in diameter (.166") and has two alternating different diameter threads, together making 18 threads per inch. The length from under the head to the end of the screw is a little over 1/2". The flange head is 1/4" hex, and has a mark indicating it was made by the Pioneer Screw and Nut Company.

I need about 25 of them. Can anyone help? This seems like a strange size, but maybe it's not?

 

After some digging, I discovered that these are #8-18 self tapping high/low machine screws.

I can find them but only in huge quantities (5-10k). Still looking for someone who will sell me 25 or 50 of these things. Anyone got a source?

 

Fastenal or McMaster-Carr ?

 

Nothing at Fastenal. McMaster has something that will work but with a different head type. If I cant find the right ones I'll get those ones.

Thanks.

 

if you are up to the challenge, i believe gm used those kinds of screws in the plastic heater/ac ducts behind the dash on many cars and trucks. maybe you could check out some local u-pullit junkyards? just a thought...

 

Have you checked Grainger?

https://www.grainger.com/content/general-catalog

 

No luck at Grainger.

 

Check out an Ace Hardware store. I doubt they'll have exactly that, but it looks familiar to other things I've seen.
Worst case, try some #8 sheet metal screws. At the factory, ease & speed of assembly, drive component selection.
However, other types can functionally work just as well -- unless you're just particular about original equipment.

Good luck.