A closed domed crown covers the protruding thread, protecting against sharp ends and corrosion while giving a finished appearance; high (DIN 1587) and low-crown patterns.
Conforms to

Domed acorn cap encloses the thread end for safety and finish.
A cross-section of stocked configurations. Not exhaustive — diameters, lengths, grades, and finishes extend across the full range on request.
Representative specifications — not exhaustive · NXB-CPN
Match the line to the load, the environment, and the standard it answers to.
Materials
Finishes
Standards
Typical applications
Served industries
Mating parts and adjacent lines engineers reach for alongside this one.
The standard six-sided nut for threaded assemblies.
M3–M48 · #4–2"
Twin wings for repeated hand tightening, no tools.
M3–M16 · #6–1/2"
Integral serrated flange spreads load and locks against backout.
M5–M20 · 1/4"–3/4"
Spreads clamp load and protects the bearing surface.
M3–M36 · #6–1-1/2"
Grade, material, finish, and standard — matched to your joint and quoted from stock. Tell us the load case and we’ll confirm the line.