The 25Z5 is an American TV rectifier. Within the envelope, sharing a common heater, are two independent rectifiers. The heater current of 0.3 Amps is one of the standard heater chain currents.
The independent rectifiers make three configurations possible: the pair as a full wave rectifier, the pair to produce 250 V from 117 V mains in voltage doubler configuration, and lastly in parallel as a half wave rectifier.
The maximum reservoir capacitor is quoted at 16 µF.
The RCA logo and the word Radiotron. The anodes can be seen side on.
The anodes face view. The cathodes are at the centre of the envelope side by side. The heat radiating fins spread to the outside where the supports are located.
The classic envelope is 38 mm in diameter and, excluding the UX6 base pins, is 88 mm tall.
References: Data-sheet & 1040. Type 25Z5 was first introduced in 1936. See also1936 adverts.
