Transmissions hydrauliques — Dimensions et exigences des raccords rapides de type à visser pour usage à une pression de 72 MPa (720 bar)

ISO 14540:2013 specifies dimensional and performance requirements for
hydraulic screw-to-connect quick-action couplings designed to be used at
pressure of 72 MPa (720 bar) in static conditions as an interface between a
hydraulic power unit and a tool. Typical applications for these couplings are
related to hydraulic jacks, rams, clamping devices, hand tools, and
cylinders.

ISO 14540:2013 covers two types of such couplings: the "P" type, which has a
poppet valve, and the "S" type, which has a spherical valve.