This document specifies dimensions for two respiratory small-bore connectors. One (R1) for use on medical devices subjected to pressures up to 15 kPa such as a breathing system, the other (R2) for use on medical devices subjected to higher pressures between 15 kPa and 600 kPa such as oxygen therapy tubing. This document also specifies the performance requirements used to verify the dimensions. This document does not specify requirements for the medical devices or accessories that use these connectors. Such requirements are given in particular International Standards for specific medical devices or accessories. This document does not specify requirements for connectors for pressurizing and depressurizing the retention mechanism (e.g. balloon) used to hold invasive respiratory medical devices in place. NOTE 1 Manufacturers are encouraged to incorporate the small-bore connectors specified in this part of ISO 80369 into medical devices, medical systems or accessories of breathing systems or respirable driving gas applications even if currently not required by the relevant particular medical device standards. It is expected that when the relevant particular medical device standards are revised, requirements for small-bore connectors, as specified in this part of ISO 80369, will be included. NOTE 2 ISO 80369-1:2018, Clause 7, specifies alternative methods of conformance with ISO 80369-1:2018, for small-bore connectors intended for use as an ancillary port connection in the breathing system or in the respirable driving gas applications of medical devices or accessories, which do not conform with this part of ISO 80369.