U50, MARCONI, BROWN BASE, JG, HAMMERSMITH JULY 1953 PRODUCTION,

CV1258, MILITARY SPEC U50, GEC-MOV, AIR MINISTRY SURPLUS, HAMMERSMITH MAY 1955 PRODUCTION

CV1258, MILITARY SPEC U50, MARCONI OSRAM, MOV, IN RST BOX, NOS, AIR MINISTRY SURPLUS, DOVER JANUARY 1953 PRODUCTION

U50, MARCONI, DOVER, DECEMBER 1952 MANUFACTURE, SCARCE

U50, OSRAM, BLACK BASE, HAMMERSMITH 1950 PRODUCTION,

U50, MARCONI OSRAM, BLACK BASE, HAMMERSMITH 1949 PRODUCTION,