The Rexroth R900504269 ZDC6P-21/V is a pilot-operated check valve designed in a sandwich plate configuration for vertical stacking assemblies. It provides leak-free blocking of the P port, ensuring that pressure is maintained securely within a hydraulic circuit. This valve allows free flow from P2 to P1 and blocks flow in the opposite direction. The block can be released by applying pilot pressure from port A or B. Engineered for reliability and performance, it mounts between a directional control valve and a subplate or manifold, conforming to the ISO 4401-03-02-0-05 porting pattern. The FKM seals (Viton) make it suitable for a wide range of hydraulic fluids and operating temperatures.