This International Standard specifies the characteristics of outlet connections for gas cylinder valves for compressed breathable air gas cylinders. It states the fundamental requirements for both; the connection and its components and includes basic dimensions. Included in this International Standard are the following connections:- yoke type outlet connection for SCUBA use up to a maximum cylinder working pressure of 232 bar;- threaded type outlet connections up to a maximum cylinder working pressure of 232 bar and 300 bar; and- threaded type outlet connection for SCUBA use up to a maximum cylinder working pressure of 232 bar including adaptor for users to convert into a yoke type outlet.Annex A gives the outlet connection type test procedures.Requirements for cylinder valves (see ISO 10297) are not covered by this International Standard.Requirements for material specifications and gas/material compatibility (see ISO 11114-1 and ISO 11114-2) are not covered by this International Standard.