Lezyne 16-Gram CO2 Cartridges Inflating your tires with CO2 cartridges is easier and more convenient that carrying around a hand pump. This product comes in a pack of five so you'll never be without CO2 in the trails. Each cartridge is 16-grams and is threaded for easy use with a CO2 inflator head. Features Five pack 16-gram, threaded CO2 cartridges suitable for high-pressure tires | Lezyne | 16G 5-Pack Co2 Refill Cartridges 16G Co2 5-Pack