Ninja Paintball Bottle Thread protectors work with all paintball CO2 bottles and HPA tanks. When attached to the bottle, these protect the threads of the bottle from damage. The thread protector includes an attached space bottle oring. Thread protectors come in several colors so you can easily identify different bottles.
Threads on bottles can be damaged very easily if dropped. CO2 valves and HPA regulator bonnets can cost $15 to $20 to replace if damaged.