First of many patent numbers printed with white ink around the circumference.
Written in fine white ink inside the envelope on the top electrode glass.
Written with a black marker on one of the mounting feet.
Printed with white ink around the circumference.
overall: 21 in x 6 1/2 in x 4 3/4 in
This is a large glass vacuum tube that has a metal ring and mounting tabs that covers the bottom one-fourth of the envelope. Three leads extend from the ceramic base of tube. One is colored green and is labeled with a 'G'; a second is colored brown and is labeled 'E+'; and a third brown lead which is made up of two conductors is labeled 'E-' Extending from the top of the tube there are two uninsulated conductors surrounded by brown varnished insulation; these connect to the same electrode within the envelope. All leads are terminated with ring lugs.