CX valve with concentric metal rings and sinusoidal springs is often used as concentric valve combined together with the AMX type. The CX valves are particularly suitable for lubricated use, at high speed (1800 rpm) and high temperatures (250°C).

They are also amongst the valves with lowest clearance. Apart from marine compressors they are also used in reciprocating compressors for large air conditioning plants and for refrigeration plants, upon request they are also provided with a safety device to prevent liquid overpressure inside the cylinder.