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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