In this type of level glass the fluid is contained in a glass tube.
The liquid level is shown by the different transparency of two phases.
The level glass is suitable for low pressure because the glass tube fragility.
The level glass is supplied with a light metallic protection for protect the glass tube from crash.
This type of transparency level glass can be employed in nearly all installation, also when are required:
a) the interface observation;
b) the liquid color observation.