AUDIO VALVES: 5Z4GT, GZ30, CV2748

Following the trend for miniaturisation of consumer and military electronics a development of the 5Z4 and 5Z4G, initially introduced in the late 1930's was made that culminated in the introduction of the 5Z4GT in early 1940.

For this variant, the glass envelope is approx 38 - 39mm in diameter with a height of 69 - 71mm excluding the base pins.