HitAir Safety Vest Replacement Co2 CanistersWe love these Hit AirPro Airbag Saftey Vest Replacement co2 cartridges because they are so quick and easy to replace. Hit Air Airbag Safety Vest Replacement CO2 Cartridges (each sold separately). Which size do I need? 48cc (Hit Air Original) 50cc (Hit Air Original Kids; Advantage XS, S, M; PRO Plus S) 60cc (Hit Air Advantage L; XL PRO Plus M, L) **Please note due to Hazmat shipping requirements these cannot be shipped expedited.** **Due to the