KLINGER sight glasses are suitable for installation in almost any type of liquid. We manufacture our sight glasses in-house using either soda-lime glass or "extra hard" borosilicate glass, which is subsequently heat-treated. KLINGER sight glasses have high mechanical strength and are exceptionally resistant to bases, acids, and boiler water (within operating limits). Our in-house glass testing laboratory conducts ongoing quality control tests: glass purity, glass defects, measurement accuracy, etc. This ensures the high quality standard of KLINGER sight glasses. We manufacture reflective and transparent glass according to the most varied international standards. The quality of the sight glass depends mainly on the chemical composition and mechanical strength. To ensure quality, the glasses are analyzed and acid/alkali tested. The mechanical strength is achieved through thermal pre-stressing
