The DH150 is also the EBC41 and is a medium impedance screened double diode triode. It would be used in signal and AGC detection in receivers. The triode would then act as the first audio amplifier stage.
The envelope also carries the Type designation EBC41.
The skirt and locating pip are moulded into the glass.
The thin glass tube envelope is 20 mm in diameter and, excluding the B8A base pins, is 52 mm tall.
References: Datasheet & 1040. Type DH150 was first introduced in 1948.