15.5mm numeric tube manufactured by National Electronics

The NL-840VR is a clear glass numeric nixie tube manufactured by National Electronics. It displays numerals from one to nine. Currently there is no more info about this tube, but it seems to be exactly the same as NL-840. Maybe this tube has some foreign specifiations or was made for a specific product. If you have any info about this tube and its usage, i'm happy to hear about it.
Brand / Manfacturer National Electronics
Same Types
Likely Tyes
Symbol height in mm 15.5
Characters / Symbols 0-9
Decimal point none
Base / Socket 0
Starting Voltage (typ) 170 V
Maintaining Voltage (typ) 0 V
Current per Segment 3mA
Reccomend Resistor 8.2kOhm @ 170V, 39kOhm @ 250V, 56kOhm @ 300V according to datasheet (NL-840)