16g CO2 capsules (or cartridges) are pressurized canisters used primarily for rapid bicycle tire inflation and beverage dispensing
. They are typically made of recyclable steel and contain high-purity carbon dioxide (E290). 
Key Types and Specifications
Threaded vs. Unthreaded:
Threaded: Most common for cycling, using a standard 3/8”-24 TPI thread to screw directly into an inflator head.
Unthreaded: Often used in specific beverage dispensers or older bike pump styles.
Food Grade: Essential for beer kegs and wine preservation (e.g., Coravin or Perlage). While many food-grade capsules can also inflate tires, non-food grade "industrial" capsules should not be used for drinks.
Dimensions: Typically ~89mm long and 22mm in diameter, weighing roughly 58g total. 
 
Safety and Handling
Freezing Risk: Cartridges become extremely cold when discharged. Use an insulated foam sleeve to prevent freeze burns.
Storage: Keep in a cool, dry place below 50°C (122°F) to avoid the risk of explosion.
Disposal: Only dispose of cartridges when they are completely empty; they are 100% recyclable.