This is a pilot operated check valve (spring closing and cone on edge seals) with a built-in flow control feature. The mounting surface is according to the ISO 4401 standard.
The CHM5 are always mounted under the ISO 4401-05 directional solenoid valves and can be assembled with all other ISO 4401-05 valves.
The pre-opening feature of the valve causes the decompression of the cylinder chamber, leading to a smooth motion.