ISO 5210:2017 specifies the requirements for the attachment of multi-turn actuators to valves. Throughout this document, "actuator" may be understood as "actuator and/or gearbox" providing a multi-turn and/or linear output. ISO 5210:2017 specifies: - flange dimensions necessary for the attachment of actuators to industrial valves [see Figure 1 a)] or to intermediate supports [see Figure 1 b)]; - those driving component dimensions of actuators which are necessary to attach them to the driven components; - reference values for torque and thrust for flanges having the dimensions specified in this document.