LM85G is a local direct-reading meter and has applied thermostable, high pressure resistance quartz glass tube. It could indicate the liquid level in tanks with high temperature, high pressure and caustic liquid directly. It contains 2 colors display-red color indicates liquid level; blue indicates that there is no liquid level. With constant indication, it is also easy to read and operate. It includes housing, red and blue glass tube, GRA, hermetic components and drain valve. According to the principle of communicating vessels, leading the medium from the vessel to the quartz glass tube and then the level could be read from the quartz glass tube.Then according to the principle of the light refraction principle, the position with liquid level will turn red; the position without liquid level will turn blue with clear division to the red area. The quartz glass tube is well protected by the metal housing and well sealed to ensure safety.