Last tested
2024
Status:ongoing
2025

Alien 4.0

Pro's choice Race
The boot of choice for many top athletes, it's a little heavier but has a more natural stride and a thick sole for taking on technical terrain
  • Buyer’s Guide reviews
  • In words
  • Technical specifications

    Buyer’s Guide reviews

    Performance by context
    Ascent
    Skiing
    Walking
    Climbing
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    The charts show our impressions from testing
    Product info
    Category average
    Recommended use
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    Recommended level
    Technical Level
    Beginner
    Intermediate
    Advanced
    High level
    Weight
    lightmedianheavy
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    In lab
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    In words

    Intro
    It's 80–100 g heavier than its closest competitors, but don't be fooled, it vies with the Stratos and DNA Pro for the most podium places in the biggest international competitions. The focus here is on functionality at all costs, even if that means taking on a few extra grams. It's best in class in terms of walkability, and has a BOA dial for the fastest possible closure, as well as a rear anti-snow gaiter. All of which help to shave valuable seconds off your race time.
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    product
    Walking
    The toes and muscles of the foot are able to contract and aid the stride, despite the incredibly snug fit, which is more precise than the Alien 1.0. Thanks to the rockered sole, walkability on dry surfaces is excellent. The rocker is easily visible, even to distracted eyes, and makes the Alien faster in transition with better traction on steep, uneven terrain. The cuff rotation is 100% free and the heel is well supported.
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    Lab
    It's relatively easy to put on with the liner already in the shell if you tip the cuff completely back. There are three pairs of pads of varying thickness that can be attached to protect the shins, while the foam is wafer thin. The liner is short but has a better consistency than its direct competitors and there are two versions available, one stiffer than the other. If you have bigger-than-average calves the cuff flap may pinch a little, but that's easily resolved by attaching a spoiler.
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    Skiing
    This boot is all about stability, aided by the snug heel pocket (be aware of this if you have any lumps or bumps in this area) and the concave shape of the base of the shell. The technical fit is accentuated by the lacing of the liner, especially on the tongue. The BOA dial locks it all firmly in place, and can be instantly adjusted at any moment. On the downhill all this translates into a good overall feel, more forgiving than that of the Stratos VI due to its lower cuff flap, giving it a deeper forward flex.
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    Technical specifications

    LINER MATERIALS
    carbon fiber
    SHELL MATERIALS
    carbon fiber
    INSERT TYPE
    Quick-Step-in
    Buckle description
    Speed Lock System with Dyneema cable + Boa Fit System
    Sole description
    Scarpa UFO LT sole in Vibram TOP 85
    Liner description
    Intuition Race 4.0 SL
    No. of buckles
    2
    Lean forward
    9°/13° - 11°/15°
    Available sizes
    39-44 EU, no half sizes (boot developed using EU sizing, the mondopoint sizes are approximate for comparison)
    Released in
    2021
    Made in
    Italy
    Price
    1999 €
    Declared specsMeasured by us
    We measured the measure 27 to get all the details
    610 gr
    Individual weight
    XXXXX
    N/A
    Liner weight
    XXXXX
    N/A
    Shell weight
    XXXXX
    N/A
    External shell length
    XXXXX
    N/A
    External shell width
    XXXXX
    N/A
    Inner shell width
    XXXXX
    N/A
    Pin distance
    XXXXX
    N/A
    Force to 20° back
    XXXXX
    N/A
    Force to 20° forward
    XXXXX
    76 °
    Cuff ROM
    XXXXX
    N/A
    Maximum cuff height
    XXXXX
    N/A
    Maximum tongue height
    XXXXX
    N/A
    Maximum forefoot width
    XXXXX
    N/A
    Maximum ankle width
    XXXXX
    N/A
    Sole thickness at toe
    XXXXX
    99 mm
    Last
    XXXXX
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