Set of 12 .551" long nickel plated steel flat phillips head wood screws for mounting USA humbucking pickup rings by Fralin, Gibson, DiMarzio, Fender and probably many other brands as well. On a sample screw I measured .551" overall length, .077" diameter on the threaded portion, .149" diameter head. Brand New.
If you're installing these on a custom build it's important that you drill pilot holes about the same diameter as the unthreaded portion of the screws. if the holes are true and straight the threads will do their job and hold the screws in place. In the photos I've used a 1/16" drill bit. A trial run with some Guitar Grease easing the way is also a good idea. The photos show the screws installed on hard rock maple. Be extra careful to mark the four mounting holes accurately or the flexible plastic mounting ring will look somewhat distorted. I use a General spring loaded center punch as starters for the drill.