1) Material quality: SUS304, SUS316L 2) Size: 1/2"-6" or DN15-DN150 3) Standard: ISO, DIN, SMS, IDF, 3A, RJT Hygienic sight glasses / sanitary flow indicators The sight glass/flow indicator is the most convenient way to visually monitoHygienic sight glasses / sanitary flow indicators The sight glass/flow indicator is the most convenient way to visually monitor & check the presence, colour and ...