original TUNGSRAM PV495 tube
  RGN1054 G1054 KL74301 506 U10
Full Wave Direct Heating Rectifier tube
Vf=4V, If=1A
made in Great Britain in 1940's

shining black plates, foil getter

probably unused tube, tested in conditions f=4V Ua=20V

very high emission

Ia = 36mA/40mA
 tube is in a perfect technical shape
you will get the tube from the pictures