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300X緩閉止回閥由主閥、單向閥、針閥、球閥、微形過濾器和壓力表組成水力控制接管系統。300 X slowly-closing check valve, check valve, by the needle valve, ball valves, micro form filters and pressure gauge up a hydraulic control over the system. With hydraulic automatic operation, can make the main valve to get the best opening or closing speed. 300 X slowly-closing check valves prevent water like water attack of generation, in order to achieve the effect of slowly-closing silencing. Red valve slowly-closing check valve with hydraulic self-reliance control, no other device and energy, maintenance is simple, open and slowly-closing smoothly. 300 X slowly-closing check valve is widely used in high-rise buildings, living quarters, water supply network system and the urban water supply project.