Moisture indicator Sg-series sight glass(moisture indicator) is a kind of element which shows the moisture and the flow of refrigerant. The content of refrigerant in the line of the system; The content of water in the refrigerant; Indicates the oil level of compressor crooked. Sg-series have indicator paper whose color changes can indicate the content of water in the refrigerant; The glasses and the fªofª ring can make sure there is no leak of the refrigerant; Max. Working pressure: 35bar (500psig); The temperature of the medium: -50f¦ f+ +110f¦; The content of water is low, the color will change blue while high it will change pink which shows that filter dryer in the system needs to be changed.