This box of 10, 8 gram CO2 cartridges is to be used with Non-QUANTUM (older) PATTI units. These units include the PATTI Jr, PATTI 2A, PATTI 3, and PATTI 110. The CO2 cartridges allow for maximum portability of the PATTI system by eliminating the need for shop air. Please contact us if you are unsure of the CO2 cartridge size of your instrument.