Byrna 8 Gram CO2 + Oiler Cartridges | 10 Count Pack | for Byrna SD/CL/HD/EP - (9 CO2 + 1 Oiler Cylinders)WHAT'S IN THE BOX: (10 ct.) 8g CO2 Cartridges. Including 9 standard 8g CO2 cartridges and 1 CO2 cartridge including oil for maintenance. EASY TO USE: Simply install the oiler cartridge like any other 8g CO2 cartridge and fire away! The CO2 with Oil cartridge does all the work while you fire. CAPACITY: Each CO2 cartridge will be good for 15 20 rounds. PLEASE NOTE: This pack of CO2 cartridges includes one marked cartridge that contains CO2 + Oil. We