The 35Z3 is a half wave rectifier that matches the 150 mA heater range of American Loctal valves. These would run directly across the mains without an isolating transformer. Low cost domestic receivers would be the target application. Possibly with line-cord as the mains dropper resistance.
The tall rectifier with the anode stitched together.
The edge view of the anode.
The wide glass tube envelope is 28 mm in diameter, and excluding the B8B base pins is 66 mm tall.