https://www.amazon.co.uk/dp/B0BNCJGHLN
Hyperbaric Oxygen and hydrogen therapy (also known as Hydroxy therapy) combines oxygen and molecular hydrogen in a pressurised environment (greater than our normal atmosphere).
In this environment, oxygen and hydrogen are dissolved into the blood plasma increasing oxygen saturation by up to 50%.
This can lead to a myriad of health benefits including healing and rejuvenation.