1. Boot Flex Rating

Ski boots come with a "flex rating," typically a number between 60 and 130+ that indicates stiffness. This isn't standardized across manufacturers, but generally:

• Soft flex (60-80) : For beginners, lighter skiers, and those who prefer a more forgiving feel
• Medium flex (85-100) : For intermediate skiers who want responsive control without excessive rigidity
• Stiff flex (100-120) : For advanced skiers who need precise power transfer
• Race/expert flex (120+) : For competitive skiers and experts who demand maximum performance

Your ideal flex depends on your weight, skill level, skiing style, and the terrain you typically ski. A boot that's too stiff will be difficult to control; too soft and you'll lack precision. This is especially important when paired with our high-performance skis like the Citadel 107 or Endurance 98, which transfer energy efficiently and benefit from a properly matched boot flex.

Note: Boots are normally available in a variety of stiffnesses; the stiffness is stated in the naming convention (example: BOOT 90 or BOOT 110). This means that the 90 or the 110 signals how stiff the boot is. 

Your foot shape, not just size, determines which last width will work best for you. Properly fitted boots help ensure you can fully leverage the responsive edge control of Renoun skis.

Note: Your width can change in a weighted stance vs. unweighted depending on the strength of your arch muscle. This can cause your foot to widen and be wider when weighted. Arch support can help relieve this and add power back into your ski while on edge. 

3. Mondopoint Sizing

Unlike regular shoes, ski boots use Mondopoint sizing – the length of your foot in centimeters. A proper fit usually means selecting boots 1-1.5 sizes smaller than your street shoes, as boots should fit exceptionally snug when new and will pack out with use.

This is why you'll see boots labeled 23.5 or 24.5 instead of size 9 or size 10. 

4. Shell Construction

Modern ski boots feature a hard plastic outer shell with a removable inner liner. Different manufacturers use various plastics that affect:

• Temperature sensitivity
• Weight
• Energy transmission
• Durability
• Ease of entry/exit

Just as we at Renoun use non-Newtonian polymers in our skis to adapt to conditions, boot manufacturers are constantly innovating with materials that provide the perfect balance of performance and comfort.

4. Instep Height and Calf Volume

Beyond width, boots vary in height and volume. High-instep feet or muscular calves may require specific models or modifications to prevent pressure points and circulation issues.

4. Walk Modes and Hybrid Boots

For those who hike, tour, or simply want comfort when walking:

• Advanced walk mode mechanisms with greater range of motion
• Lighter weight materials and construction
• GripWalk and WTR soles for improved traction
• Some models feature tech inserts compatible with touring bindings
• Varying degrees of compromise between uphill and downhill performance
• Excellent companions for our Citadel touring skis when venturing beyond resort boundaries

5. Heat Moldable Shells

Beyond just moldable liners, some manufacturers now offer:

• Shells that can be custom-molded using heat
• Typically requires professional equipment
• Allows for more dramatic fit customization
• Examples include Fischer Vacuum and Atomic Memory Fit technologies

6. Smart Boot Technology

The newest frontier in boot technology:

• Integrated heated liners with smartphone control
• Pressure and performance sensors for data analysis (CARV) 

Custom Footbeds

Perhaps the most important upgrade, custom footbeds provide proper alignment and support that stock insoles simply can't match. Boot fitters can create these based on your foot structure, improving both comfort and performance. At Renoun, we've found that custom footbeds dramatically improve energy transfer to our skis, allowing you to fully experience the performance benefits of our VibeStop™.

The Intangibles

Real-World Experience

Boot fitters have worked with countless feet and can recognize potential issues before they become painful problems. Their experience with different brands and models provides insight no online review can match.

Long-Term Relationships

A good boot fitter will offer follow-up adjustments as your boots break in, ensuring continued comfort throughout the life of your boots.

The Cost Perspective

While professional boot fitting adds to the initial investment, consider:

• The cost of replacing hastily purchased, uncomfortable boots
• Lost skiing days due to foot pain
• Performance limitations from ill-fitting equipment
• The value of enjoying every moment on the mountain without distraction

We at Renoun understand the value of investing in quality equipment. Most experienced skiers will tell you: boots are the one piece of equipment where investing in professional help pays dividends with every turn.

Once you've found your perfect boots, consider how they'll work with different Renoun models:

• Citadel: Our most powerful powder/backcountry skis benefit from boots with hybrid capabilities with a lighter weight feel. You'll want enough lateral stiffness and precision for aggressive skiing in challenging conditions.
• Endurance: These versatile all-mountain performers pair well with mid-flex boots that balance precision and comfort.
• Atlas: Our carving focused, playful, nimble skis work wonderfully with boots that offer good flex and quick response.
• Earhart: These light weight-oriented models benefit from lightweight boots with light to medium stiffness.