These are Acorn Nut Screws. They are also referred to as "Luke Rivets" for knife handles. Acorn Nut Screws are 3-piece threaded fasteners that work extremely well for knife handle attachment. With this design, you will create a step hole in your handle material that is slightly larger than the shank of the threaded rod. The three-part assembly allows for you to pass the threaded rod precisely through your knife tang hole and handle material, allowing the larger radius of the heads to create a pinch points on both sides of the handle material, where it can then be tightened down to a secure hold. Once the threaded heads have been tightened, they can be sanded to a flush finish with the handle surface. This will result in a smooth, pin-like visual effect on the final knife handle. When used with epoxy and/or thread-locker adhesive, they will create a permanent handle bond.
Head Diameter = .186 in. (ea.)
Head Length = .350 in. (ea.)
Thread Depth = .1875 in.
Thread Diameter = .110 in.
Thread = US 4-40
Threaded Rod Length = .650 in.
Overall Length (min) = (.90 in)
Overall Length (max) = (1.1 in)
Driver = Slot
Material = Brass
1 Acorn Nut Screw Fastener = (1 Threaded Rod + 2 Threaded Nuts)