This document is applicable to pin-index yoke-type valve connections for medical gas cylinders, with a working pressure up to a maximum of 200 bar or test pressure up to a maximum of 300 bar, or both. NOTE 1 This type of connection is primarily used for small cylinders (5 l or below). NOTE 2 In this document the unit bar is used, due to its universal use in the field of technical gases. It should, however, be noted that bar is not an SI unit, and that the corresponding SI unit for pressure is Pa (1 bar = 105 Pa = 105 N/m2). This document specifies: basic dimensions; requirements for alternative designs of the yoke-type valve connections; dimensions and positions for the holes and pins for the outlet connections. It also specifies the dimensions and positions for the holes and pins for the outlet connections for gases and gas mixtures.