O-Ringisatypeofagasketorasealintheformofaringwithacircularcrosssectionusedtopreventleakageoffluids.ThisO-RingismadeupofEthylenePropyleneRubberwhichisasyntheticelastomerknownforresistanttoheat,oxidationandozone.O-ringsactsasagoodleakbarrierandarewidelyusedinmedicalequipments.O-Ringisdesignedtobeseatedinagrooveandcompressedduringassemblybetweentwoormore parts,creatingasealattheinterface.ThepackageoftheO-Ringcomeswithamarkthatthecontentshavebeencleanedforbreathingcircuitgas.ThisO-RingiscompatiblewithAespire100,Aespire7100,Aespire7900andAestiva7100AnesthesiaDeliverysystem.