Set consists of four nickel plated steel round phillips head #3-48 X 1.083" long machine screws and four nickel plated steel compression springs. On a sample screw I measured .171" diameter. On a sample spring I measured 1.15" overall length, .176" diameter. These parts fit most Gibson, Fralin, Dimarzio and many other standard USA humbuckers. Check the thread size in the base plate of your pickups before you order. Great for repairs to working guitars without spending an arm and a leg.