This exhibit is a 12AU6A RF pentode for use up to 50 MHz. Apart from the heater all characteristics are the same as the 6AU6. The A variant has defined heater voltage and current specifications and is rated for AC or DC. DC being vehicle battery supplies.
The warm-up time is 17 s.
This Tektronix label shows that this type was used in professional test equipment.
The letters IC for General Electric can be seen to the right of the Tektronix label.
The thin glass tube envelope is 18 mm in diameter and excluding the B7G base pins the valve is 49 mm tall.
