Firm yet somewhat forgiving, the Flex Booster 1K enables you to customize a boot’s flex and support. It makes a boot slightly stiffer and more responsive by increasing its flex rating by one point. Forget the gym—get the results you need with the Flex Booster 1K.
Size S 21.0 – 24.5  |  Size M 25.0 – 27.5  |  Size L 28.0 – 33.0
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Thanks to its stiffer flex, the Flex Booster 2K enhances a boot’s support and response significantly by increasing its flex rating by two points. With the Flex Booster 2K, you can enhance your performance—without breaking the law. .
Size S 21.0 – 24.5 | Size M 25.0 – 27.5 | Size L 28.0 – 33.0
Especially stiff, the Flex Booster 3K makes a boot incredibly supportive and exceptionally responsive by increasing its flex rating by three points. Skip the gym and ditch the weights—the Flex Booster 3K is all you need to max out your ride.
Size S 21.0 – 24.5  |  Size M 25.0 – 27.5  |  Size L 28.0 – 33.0
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