This is a power pentode in a glass envelope with an eight-pin loctal base. A ring was drawn in red ink around the top of the envelope. This is a spare tube for Bus Driver Flip-Flop Storage Rack S/N 6.
Date
1959 ca.
Manufacturer
Sylvania
Place Manufactured
U. S.
Identifying Numbers
WAD18
Handwritten in red ink near the bottom of the glass envelope.