Product Overview CRL\’s Acorn Cap Nut for 1-1/2\” and 2\” Standoffsare commonly used for applications that need a finished top. They are intended for use during installations when using the 3/8\”-16 size Allen screw or threaded rod accessories of our standoff system. The acorn cap nut is used to tighten the Allen Screw or threaded rod into a wall anchor to protect the threads, then it is removed prior to installing the standoff base. NOTE:Allen screws or threaded rods must be installed to proper length during installation for Acorn nut to fit properly. Protects Threads During Installation of Allen Screws or Threaded Rod Improves Quality of Standoff Installation 304 Stainless Finish