Factory Stag 10 handguard screws

[Backwoods]

I need a screw for the factory handguard.

There are 8 I think at the receiver end, and one fell out.

Looks like a simple machine screw, anyone know what thread or size?

I'll take the upper and handguard into a bolt place where I know a guy if I need to, but it'd be easier to just know the threads and size.

Thanks in advance.

 

[Bile]

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