Long-life submarine repeater valve type 10P2, developed at Post Office Research Station, Dollis Hill, London, England, 1950-1960. The glass is engraved with signatures of research team at the time. Names inscribed on the valve are: R E. Hines; H. N. Daglish; M. R. Child; J. Aucherlonie; J. H. Reynolds; C. B. Johnson; R. W. Lawson; M. W. Rogers; M. F. Holmes; E. F. Rickard; E. Woodgate; H. Batey; E. Metson; H. P. Sargent; and C. Hardman

This valve is from a stage in the development of the submarine repeaters that would go on to be used in CANTAT 1, the first transatlantic telephone cable connecting Britain and Canada. The object was presented as a memento to a founding member of the Thermionics Group at Dollis Hill when he went to take up another post. It is inscribed with the names of the research team at the time.