Fits regulator size 1-3/16” x 5/8” or 3.02 cm x 1.59 cmAerisAqua LungCalypso, Core, Titan (Titan LX is a 4), Legend, Kronos, and MikronAtomicmanufactured post-2005, Z2, Z3, B2, T2X, T3, M1, ST1BeuchatVS3, VS4, VS8, VX10CressiEllipse, Master CromoDacorViper and EagleDeep 6 Signature SeriesDGX Gears D6Dive Riteincluding O2ptima rebreather, but not the Jet Stream 4500EdgeHog and EpicForteGenesisHalcyonrebreather and regulatorsHollisregulators (except 500SE is a 4)IDI Regulatorsno longer in business (all but Osprey which is a size 1)Maresnot MARES MR-12-II, III, IV or VOcean EdgeOcean ReefOceanicincluding the Alpha 10 (cannot fit Alpha 9 or Omega 3)OdysseyScuba MaxSCUBAPROA700, C-series, C350, C370, G250, G260, R195, S270, S620Ti, D420Sea EliteSherwood9000 Series, Maximus, SR1, SR2, 1992 and newer Blizzard and OasisSporasubSUBGEARSG50, SG30, SG10, Aruba, and BonaireTigullioTilosXS ScubaInspire and Brawn (Tested at Manufacturer)Zeagle F8