New Nike patent just granted: Footwear with integrated biased heel fit device Quote: A shoe structure specifically designed to more securely fit a wider range of feet widths and proportions by providing an integrated resilient heel device in the rearfoot region of the upper. The heel device extends upward and rearward toward the back of the foot to avoid the bulbous end of the calcaneus but also to engage the area just above the heel bone. The heel device has opposing portions that are biased toward one another and provide a secure but comfortable engagement of the shoe onto the wearer’s heel
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Footwear with integrated biased heel fit device