Machined aluminum construction is both lightweight and highly durable. Hardened steel reamer scours hole, inserts plug and inflates tire for an efficient and rapid repair. CNC-machined twist knob manually controls release of CO2 gas. Aluminum canister holds the five included tire plugs and safely stores the reamer when not in use. High quality tire plugs aggressively seal holes that are too large to be sealed by sealant alone (hole size varies from tire to tire). Sleek, compact design fits in a pocket or straps to your bike. Two kit options: Two 20-gram CO2 cartridges or no cartridges, and a simple Velcro strap.