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Sidas·Ski boots·Accessories Ski Boots
5,0(1 ratings)

Sidas Volume Reducer 5mm Hard

5 mm volume reducer that gives a tighter fit and better foot support in the boot.

18 €
1Size
18 €
  • Delivery in 2–5 business days
  • 30-day returns
Ski expert
Not sure about the size? Chat with a ski expert, or call +46 370 33 97 70.
5 mm
Thickness
Five millimeters thick volume reducer for an adjustable fit.
Better support
Foot support
Reduces space in the boot and gives your feet better support.
Trimmable
Trimming
Can be trimmed to fit a smaller size precisely.

About Sidas Volume Reducer 5mm Hard – Accessories Ski Boots

The Sidas Volume Reducer is a volume reducer that is placed under your insoles to provide a more precise fit in your ski boots. It reduces space and provides better foot support, resulting in higher precision and increased comfort when skiing.

This model is 5 mm thick, allowing you to easily adjust the volume as needed. You can also trim the insole to fit a smaller size and achieve a perfect individual fit.

Sidas Volume Reducer, Size Guide

  • XS: 35-36
  • S: 37-38
  • M: 39-41
  • L: 42-43
  • XL: 44-45
  • XXL: 46-48

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.

Customer reviews

5,0 · 1 ratings · 1 review
5,0

1 ratings · 1 review · 100% give 4–5 stars

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Verified reviews via Lipscore

★★★★★Apr 2026

Räddade ett par " plaskpjäxor".

Per-Henrik L✓ Verified purchase·Purchased: M / Vit

Sidas Volume Reducer 5mm Hard specifications

CategoryAccessories Ski Boots
Thickness5 mm
Available sizesM, L, XL
AdjustmentCan be trimmed
Rating 5,0 · 1 ratings
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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.
Ski expert
Didn’t find your answer? Call +46 370 33 97 70 or chat with a ski expert.
Sidas Volume Reducer 5mm Hard
Select size
18 €