The XNP12 is a cold cathode numerical indicator tube. The Hivac name for these indicators is Numicator. The gas filling is neon to give an orange glow.
The open mesh anode with the shaped cathodes behind.
The cathodes are stacked so that each numeral appears in the same place as seen from the front.
The thin glass tube envelope is 18 mm in diameter, and excluding the base wires is 43 mm tall.
References: Adverts in the museum. Type XNP12 was first introduced in 1960.
Updated July 26, 2017.