This is the upper section of a two-part assembly that connects to a lower handle or lever assembly. Not always used with G-U or Ferco levers or cylinders. Related G-U parts: 6-25916-40-0-1 ALU-JET insertable gear 180 degrees Lever, 1-9/16" (40mm) Backset; 6-25918-40-0-1 Lock with Profile cylinder Bore, 1-9/16" (40mm) Backset.
eBay