Fusite uses its leading-edge glass-to-metal (GTM) sealing process to create highly compressed seals for hermetic sight glasses used as windows for visual level and flow indicators in high-pressure or vacuum applications. We offer a variety of bolt-on, weld-in, and threaded configurations. Standard models include single port glasses for simple level checking and multiple port glasses for more complex systems. Sight glasses can be used to check liquid levels in pumps, compressors, or other components requiring visual level or flow checks. Typically sight glasses utilize thread and hexagon bodies for flat gasket seals, with flange-type bodies for bolt mounting for ”O” ring seals, and also for solder mounting and resistance welding.