sold out quick view Call for Availability Pre War Radiator Cap (E55812) MSRP: $175.00 NEW and MINT ROLLS ROYCE RADIATOR CAP This radiator cap came from a London Pre-war Rolls Royce Factory Distributor. The bottom inside diameter is 1-15/16". Height 7/8". The chrome on this cap is beautiful. 1922-1929 20 HP 1960-1925 Silver Ghost... Call for Availability