Cap nuts are hex nuts with a domed cap on top. They are typically used as a decorative finish to cover up with studs or threaded bolts that are sticking out. KD Fasteners, Inc.® supplies the typical acorn cap nut and rubber cap nuts. Acorn cap nuts have a dome shaped end at the top. Acorn cap nuts can come either completely closed or we can supply them with an open end cap (with hole on top).
We carry them in brass, plastic, steel with a nickel plate, 18-8 stainless steel, steel black oxide, plain steel, and black zinc. Our acorn cap nuts start at 4-40 and go up to 1”-8 thread size. KD Fasteners, Inc.® also supplies metric acorn cap nuts per DIN 1587. We can supply acorn nuts with a washer base for both open and closed acorn cap nuts.
We also supply cap nuts with a rubber cap on top as opposed to a one piece acorn cap nut. We supply them steel zinc and carry them starting at 4-40 and up to ½” thread size.