How to choose reflex level gauge glass ?

Reflex Level Gauge glass uses prisms to show the level of liquid inside a vessel.

Its interior is divided into two zones: one for liquid, one for gas.

When light rays strike the surface of the Reflex Gauge Glass, it is bent to a 45-degree angle.

This specific angle has a different effect on each zone. Whereas gas/vapor will reflect the light and emit a bright silver glow,

the liquid will refract the light and appear dark.

This stark contrast between light and dark helps the person monitoring the vessel to get an accurate reading of the level of liquid inside.