PB1/Puritan 750 - Fits most Cessna singles 1980 and later and most Cessna Twins 1970 and later, and most Diamond Aircraft.
PB2/Puritan 566 - Fits most Cessna singles prior to 1980 and most Cessna Twins prior to 1970.
Scott - Fits most Beechcraft, Piper, Mooney and other GA
Aerox - Fits Aerox Portables
SkyOx - Fits SkyOx Portables
CPC - Fits Cirrus with OEM Oxygen System