The FDS80/50 double-sided locks are commonly used to control the dry jacks of hydraulic supports. This valve is installed on the flat plate of the dry jacket, the high-pressure liquid directly enters the piston cavity of the dry jacket and the piston rod cavity through two holes A and B, respectively, so that the movable support cavity is stretched or squeezed, when the action stops, the high-pressure cavity can be blocked. The optimized design of traditional valve, valve and dome are installed in one, compact design, insertable valve core, convenient maintenance. This valve has two threaded safety valve interfaces. At the same time, this valve is still a tubular connection, the high-pressure liquid through the two holes A and B directly into the piston cavity of the jacket and the piston rod cavity, respectively, so that the piston rod is stretched or squeezed, when the action of the high-pressure cavity stops and can be blocked. For traditional valve optimized design, insert valve core, convenient repair, small size, compact design, no safety valves installed. Specifications Rated Pressure: Rated Flow Rate 50Mpa: 80L/min Material: Medium Carbon/Stainless Steel/1 Cr18Ni