I think this is possibly a 14HP Crossley radiator cap.The Dia. is 1-7/8". It has a 20TPI thread.The bakelite part is excellent, the base has a nick to one edge, but it should still screw onto a radiator.I can post this and I accept PayPal.
Original Molsheim Bugatti Schraubstock Nr. 52 (Matching Numbers!)
**Historisches Meisterwerk der Automobilgeschichte: Originaler Ettore Bugatti Werkstatt-Schraubstock („Bugatti Vise“) aus den 1920er Jahren – Matching..