visual reading, two color meter, Red for liquid, White for air, simple instruction Level meter is made from colorful ... degree CWorking pressure: less than 1.6MPaCode: D for standard type, W for Warm keeping typeWarm keeping type allowed steam pressure less ... than 0.3MPaMeter matirial: I for carbon steel, II for 1Cr18Ni9Ti, 304, 316Connection: A for female flange; B for male flange; C for thread G3/4"