If you're fooling around with trapeeze tailpiece and hinged vibrato units you need good screws to mount them. These screws are getting to be hard to find in bright nickel so we bought a boatload of 'em. I measured overall length .783", head diameter .214", diameter on the main threaded portion is .123", unthreaded portion of shank is .102". Approximately .425" of the shank is threaded. Some installers prefer this style of screw to one with threads all the way up because it doesn't bite into the tailpiece or vibrato hinge hole and passes cleanly through most hollow body guitars into an interior block.