Scarpa Alien 1.0

While the Alien 1.0 is designed for competitive ski mountaineering, it works for dedicated backcountry skiers who prioritize speed and weight above all else. However, because it is a specialized race boot, it lacks the comfort and insulation features found in traditional touring boots, so it is best reserved for fast-and-light missions rather than long days in cold, resort-style conditions.

The 75-degree range of motion is a significant advantage on the skin track, allowing for a natural, long stride that mimics walking in a trail running shoe. This range helps reduce fatigue over long ascents and steep switchbacks, making your movement feel much more efficient.

Despite its 735-gram weight, the carbon-reinforced cuff and 110 flex provide surprising lateral stiffness and power transfer. It won't feel like a heavy alpine boot, but it offers a responsive, precise connection to your skis that is more than capable of handling demanding descents at speed.

The BOA Fit System on the Alien 1.0 is designed for precision and reliability, allowing you to dial in a secure fit quickly even with gloves on. While it is durable, it is always a good practice to clear any packed snow from the dial mechanism before tightening to ensure a smooth, consistent closure.

The 99mm last is considered a medium-to-narrow fit, which is standard for race-oriented boots that prioritize power transmission and a locked-in feel. If you have a wider foot, you may find the fit quite snug, so we recommend trying them on with thin race socks to gauge the volume accurately.