These mountaineering boots are designed for high altitudes, ranging from 6000m to 7000m. Please refer to the La Sportiva website for detailed specifications. Purchased in 2024, these boots were used in October of the same year for climbing Ama Dablam (6812m) in the Himalayas. During the climb, there was some damage that required repair (see note). They were repaired by the manufacturer after returning home, but some scuffs and dirt from use remain (see photos). They will be delivered in the original box. The size is EU43. I usually wear La Sportiva NEPAL CUBE EU42 for winter mountaineering, but it's advisable to go one size up for high altitudes due to foot swelling. However, I recommend trying them on at a mountaineering shop beforehand (and maybe buy something while you're there!). Frankly, they are not easy to put on and take off, but the insulation is excellent. The insoles are included, but you may want to purchase ones that better fit your feet. Note: The BOA system dials on these boots are exposed on the outside of the gaiters. These were damaged by contact with rocks during rock climbing, so both dials were replaced. Also, the front of the gaiters were damaged by friction, and the damaged areas have been repaired with black patches (same shape on both sides) (see photo 3). This could be seen as improving abrasion resistance, but please refrain from purchasing if you are concerned about these points.