Russian IN-21 nixie dot tube. It's perfect for clock projects as a colon separator. Also can be used for any other application that requires small and nicely glowing light.
Glow color: orange-red;
Brightness: > 100 cd / m²;
Power supply voltage: 220V;
Support discharge when powered: 60-90V;
The occurrence of discharge at a voltage: 110V;
The current display: 0.5 - 1.5mA;
Warranty life: > 3000h;
Tube size: 10 x 36mm.