The Salomon X-Pro R90 is an excellent ski boot for the intermediate to advanced skier looking for comfort and performance. The 360-Degree Custom Shell is a simple fit solution for the Authorized Salomon Dealer who has a special oven used to heat the shell. Once the shell is hot enough a bootfitter will place the boot on your feet. When the shell starts to cool down it can stretch and mold to match the shape of your foot for a perfectly dialed in fit. Salomon's TwinFrame2 Technology uses a lighter and stronger plastic on the sole and spine that improves your responsiveness and control. The R90 has the trademark 24mm Oversized Pivot that adds a strong connection to the upper cuff to the lower shell that enhances power transmission to your skis. The My Custom Fit Liner has heat moldable properties in the heel and ankle pocket that adds to the customization, comfort and performance. Best Fits Most Foot Shapes After Molding Process, and a Medium Calf Volume, 360-Degree Custom Shell, TwinFrame2, 24mm Oversized Pivot, My Custom Fit Liner, Flex Adjuster, 35mm Strap, Actual Flex: 90, Cuff Alignment: None, Warranty: One Year, Ski Boot Width: Medium (99-101mm), Flex: Medium, Forefoot Width: 100mm+ Custom Shell, Flex Adjustment: Yes, Buckle Count: 4, Category: Downhill, Ski Gear Intended Use: All Mountain, Instep Height: Medium, Calf Volume: Medium, Skill Range: Beginner - Advanced Intermediate, Model Year: 2019, Product ID: 570058, Model Number: L39949100255, GTIN: 0088964532694