My personal experience with ‘single leather’ mtn boots above 6km is not advisable. If you are ‘fast and light’ you can get away with it in the warmer months/regions, and with the use of liner socks and a vapor barrier. But even then if you get stopped or slowed due to issues you are going to suffer. And in -30 forget keeping your toes if you are forced to spend a night in your boots. I would bump it up to the Phantom 6k, and the advantage of the removable (hence dryable) liner… and extra warmth. These boots still WAY out perform regular plastic double boots for walking and tech climbing.

My personal experience with ‘single leather’ mtn boots above 6km is not advisable. If you are ‘fast and light’ you can get away with it in the warmer months/regions, and with the use of liner socks and a vapor barrier. But even then if you get stopped or slowed due to issues you are going to suffer. And in -30 forget keeping your toes if you are forced to spend a night in your boots. I would bump it up to the Phantom 6k, and the advantage of the removable (hence dryable) liner… and extra warmth. These boots still WAY out perform regular plastic double boots for walking and tech climbing.