9 bottles of oxygen per climber. This allows us to use high-flow oxygen sleeping at Camps 2, 3 and 4, and to climb on a higher flow than other expeditions (2L from North Col-C2, and 4L from C2-C3, C3-C4, and C4-Summit-North Col), maximizing safety and success. Our Sherpa also climb and sleep on oxygen, which means they have more strength to focus on you and your ascent.