Cold cathode counter
VOLTAR MK-70 Precision numeric instrument
Tube bank A Calibration steady
86
84
80
81
89
87
Anodized faceplate
Dark metal, warm discharge

The only color that heats up is the numeral. Everything else stays matte, measured, and recessed.

Signal path
NM640
VDC170
ERA70
Cathode intensity
Soft grid, hard chassis
This is the Nixie Tube Display design system, applied by Curio Design — a design-style library for AI agents. Full Nixie Tube Display guide → designbycurio.com/learn/calculator-nixie-tube-1970