... of glass bulb, copper alloy and sealing pieces.Sprinkler frame is refined from copper alloy what makes ... bulb is fast, reliable and sensitive. Technical Parameter: Sprinkler threaded and flow characterNominal DiameterConnecting threadedFlow CoefficientK15mm, 1/2inch ... R1/280±420mm,3/4inchR3/4115±6 Sprinkler modelZSTZ15-57ZSTZ15-68ZSTZ15-79ZSTZ15-93ZSTZ15-141ZSTZ15-182Rated Operation ...