The modular or sandwich valve is stacked along with directional valves in CETOP 3 interfaces to provide a dual pilot operated check valve system. The valve can be used to either lock one of two single acting cylinders in place or provide locking of both ends of a double acting cylinder.

Flow to either of the actuator ports (A or B) allows free flow across the check valve while the poppet opens the opposing check valve to allow return flow. The return flow of one line is blocked unless there is pressure in the opposing line.

Sandwich construction offers a compact solution. Hardened working parts ensure a long, reliable and trouble-free life. The cartridge construction gives flexibility in servicing.