The EM87/6E2 tuning indicator uses the closing bar principle and is housed in a standard miniature valve envelope.
Unlike EM87 that has a rectangular screen, this exhibit has a rounded top to the screen column.
The heater and cathode are on the right and are positioned horizontally in this image. The wires from the base pins look to be copper. At full size the heater can be seen as three hairpin loops. The cathode is shaped with a small section directed at the screen, the larger body of the cathode tube houses the heater.
The shaped cathode allows a larger surface at the back of the cathode to be used for the triode amplifier section.
The thin glass tube envelope is 22 mm in diameter and, excluding the B9A base pins, is 62 mm tall.
References: Datasheet & 1040. Type 6E2 was first introduced in 1961.