#6-32 x 5/16" Pan Screw With Locking Washer
Ships from US and is sold by Pinball Life$0.10
This screw and locking washer is commonly used on most pinball machines to fasten various items to the playfield.
Comes with locking washer.
Often used with the #6 M/S flat washer (sold separately).
Williams/Bally reference #4006-01003-05.