Oxygen Aid is an affordable and versitle oxygen canister than be used by anyone for different purposes such as altitude acclimation, sports recovery or general health and wellness. This two pack includes two different mask types to better fit your specific use case. If you're on to go and looking to recover faster - go with the cap mask. If you're at home or lounging - use the oxygen mask. Recreational oxygen is meant to help when you find yourself winded or wanting to breathe better. Oxygen Aid is here to help.