The data-sheet states that the UV199 is a hard vacuum triode for use as an amplifier or detector. It features a thoriated tungsten filament.
The bayonet base locating pin on the left.
The short base pins designed to make contact with the springs in the base of the valve-holder. The envelope carries the GE logo and the base cap has the RCA letters. This is from the period when RCA was established from other major American companies.
The GE logo etched into the envelope.
The wide glass tube envelope is 25 mm in diameter and, excluding the UV base pins, is 77 mm tall.
Reference: Data-sheet. Type UV199 was first introduced in 1923. See also1923 adverts.
