What does flex mean on ski boots?

Flex describes how stiff the boot is when you bend forward. Lower numbers are softer and more forgiving, higher numbers stiffer and more precise at speed; around 100 is an all-round level for experienced skiers. The number isn’t standardised between manufacturers, so compare within the same brand.

What is the last and which one suits me?

The last is the boot’s width across the ball of the foot — narrow about 98 mm, medium about 100 mm, wide about 102 mm. A medium last suits most people. The shell can be heat-moulded for more room.

What’s included in a boot fitting?

We analyse your foot, fit the boot, heat-mould the liner and grind or punch the shell where it pinches. Buy your ski boots from us and boot fitting is free for 1 year from purchase — you only pay for materials, such as a custom-moulded footbed. You’re welcome to drop into our store at Isaberg, Sweden for up to 1 year after your order is placed.

Do I need a custom footbed?

The standard footbed works for most people with a normal foot. A custom footbed is moulded to your footprint and gives better heel hold and less fatigue — it’s the single biggest fit improvement you can make without changing boots.

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Salomon·Ski boots·Alpine ski boots

Salomon S/Pro Supra 120

High-performance alpine ski boot for men with a regular last and moldable 4D liner for a precise fit.

568 €

1Size

2Add accessories7 products

3In-store boot fitting0 €

568 €

Delivery in 2–5 business days
30-day returns

Not sure about the size? Chat with a ski expert, or call +46 370 33 97 70.

Medium last

Fit

Regular last width that fits a wide range of foot shapes.

4D CustomFit

Liner

Moldable liner in latex foam and Talyn shapes to your ankle.

3D Instep

Entry shell

Reduces pressure when stepping in, making entry and exit easier.

About Salomon S/Pro Supra 120 – Alpine ski boots

The Salomon S/Pro Supra 120 is a ski boot that will truly provide an exceptional fit and performance. They will definitely give you an unparalleled skiing experience. These boots are designed to enhance performance and comfort, partly by reinforcing foothold and improving power transmission to the skis.

These boots are fully customizable, meaning they will fit regardless of the shape of your feet. They also feature 3D instep shell technology which minimizes pressure at the instep, making them easier to put on and take off.

The 100mm last means it's a "normal width" last, making the Salomon S/Pro Supra 120 suitable for many different feet. Here, skiers can enjoy a high-performance boot with a comfortable medium last. The 4D liner construction with latex foam and Talyn® material can be molded to perfectly conform to the contours of the ankle, providing a customizable and precise fit.

The second shell buckle from the bottom, placed at a 45° angle, is made of thinner plastic material, which reduces pressure on the top of the foot and makes it easier to step in and out. Overall, this is a truly high-performing boot that will suit many feet. A great boot that you will enjoy for many years!

Salomon S/Pro Supra 120, specifications:

Last: 100 mm
Flex: 120
Weight: 1925 grams
Polyolefin|Polyurethane Custom Shell HD
Men's
Walk Mode: No
Gripwalk: Yes
Liner: My CustomFit 4D Pro|Sensitive² Footbed
3D Instep Shell
Screwed Energyzer Velcro Strap (45 mm)

Fit & last

The last is the boot’s width across the ball of the foot. 100 mm is a medium width and suits most people. If you have a wide foot or high arches, we can spot-heat the shell in the store where it presses. The boot should feel snug when you try it on: your toes touch the front when you stand straight and pull back when you bend your knees. The liner packs out 3–5 mm during the first week, so a boot that feels comfortable in the store will be too big after a week. Always measure mondopoint — boot size has nothing to do with your normal shoe size.

Boot fitting

Buy your ski boots from us and you get free boot fitting for 1 year from purchase. That means we heat-mould the liner and grind or punch the shell at no extra charge. If we need to add materials or products, such as a custom-moulded footbed, you only pay for those — not for the work. You’re welcome to drop into our store at Isaberg, Sweden for up to 1 year after your order is placed.

Shipping & returns

Delivery time: 2–5 business days to Germany, from our warehouse in Hestra, Sweden. If the boot doesn’t fit right, free boot fitting is included for 1 year from purchase. Call +46 370 33 97 70 if you’re unsure before you order.

Often bought with Salomon S/Pro

Accessories that improve the fit

No More Boots Boot Bib

No More Boots · Ski Boot Accessories

12 €

Atomic Boot & Helmet Bag

Atomic · Bags

38 €

BootDoc Power Fit Socks

BootDoc · Ski Socks Unisex

23 €

Therm-ic Toe Warmers

Therm-ic · Accessories

5 €

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Choosing ski boots

Your ski boots affect your skiing more than any other piece of equipment — and they’re the hardest to choose online. Below we go through mondopoint, flex, last and what a boot fitting does.

Mondopoint — measure your foot, not your shoe size

Ski boots are sized in mondopoint, which is the length of your foot in centimetres. Stand with your heel against a wall, mark your longest toe and measure. That measurement is your size. Your EU shoe size is a poor starting point because it varies between manufacturers. A ski boot should feel snug when it’s new — the liner packs out 3–5 mm during the first week of skiing.

Flex and what the number means

Flex describes how much force it takes to bend the boot forward. 60–90 is soft and forgiving, 90–110 is an all-round level, 110–130 is stiff for skiers who ski hard, and above 130 is race level. The number isn’t standardised between manufacturers, so a 100 from one brand can feel like a 110 from another. If you’re heavy or ski aggressively, you want a stiffer boot; if you’re lighter or a beginner, you want a softer one.

Last — the width of your foot

The last is the boot’s width across the ball of the foot. Narrow is around 98 mm, medium around 100 mm and wide around 102 mm. A medium last suits most people. If you have a wide foot, a last that’s too narrow isn’t something you get used to — but the shell can be heat-moulded to make room where it’s needed.

Boot fitting makes the difference

Nine out of ten skiers have something adjusted at their first fitting. We analyse your foot, heat-mould the liner and grind or punch the shell where it pinches. A custom-moulded footbed gives better heel hold and less foot fatigue, and is the single biggest improvement you can make without changing boots. Buy your ski boots from us and free boot fitting is included (materials such as footbeds are paid separately), and you’re welcome to drop into the store for up to 1 year after your order is placed.

Socks and fit go together

A thin, knee-high ski sock with no seams across the ball of the foot is the right choice. Thick socks make the boot tighter without making it warmer — it’s the air inside the boot that insulates, and a boot that pinches gives you cold toes. Never wear two pairs.

Frequently asked questions

Ski boots are measured in mondopoint, which is the length of your foot in centimetres. Put your heel against a wall, measure to your longest toe and choose that size. The boot should feel snug when it’s new.

Didn’t find your answer? Call +46 370 33 97 70 or chat with a ski expert.

Salomon S/Pro Supra 120

Select size

568 €

Salomon S/Pro Supra 120

About Salomon S/Pro Supra 120 – Alpine ski boots

Salomon S/Pro Supra 120, specifications:

Fit & last

Boot fitting

Shipping & returns

Salomon S/Pro Supra 120 specifications