The QQE03-20 is a double beam transmitting tetrode. The design is of the European pattern with a single central assembly and two top supported anodes. The valve is equivalent to the QQV03-20.
The literature does not give any actual differences between the two designations and so it appears to be the way the heater connections are defined: 12.6 V centre tapped or two 6.3 V heaters that can be connected in series.
This exhibit has a crack across the base and the vacuum has been destroyed. The getter having turned white is a clear sign of a damaged vacuum.
The anodes are held only by the top of the envelope. The extra glass providing additional strength. The later design of the QQV03-20A uses sintered glass top and bottom.
The anode curve is echoed in the screen grid and beam plate shape.
The sintered glass base.
The wide glass tube envelope is 44 mm in diameter and, excluding the B7A base pins, is 72 mm tall.
Reference: Data-sheet. Type QQE03-20 was first introduced in 1957. See also1957 adverts.