KNOW YOUR TECH breaks down the scientific technology used in your favorite sneakers and activewear. Let’s demystify your next purchase: today’s technology is Asics P.H.F. (Personalized Heel Fit). Implemented into the heel collar of many Asics performance models, this custom-fitting molds provides comfort and reduced slippage/irritation.

What is it? Two layers of memory foam in the heel collar which combine to mold to the wearer's foot, creating a truly personalized feel and fit. 

How does it work? The more you wear Asics models equipped with Personalized Heel Fit, the more customized it becomes. This allows for a soft, padded feel in the heel area while also delivering a snug, contoured fit around the heel and ankle. Due to the memory foam construction, it won't wear out or degrade overtime; each time you put on a pair with P.H.F, you'll notice its glove-like, heel-wrapping fit.

Notable products: GEL-Blur33 TR, GEL-Cumulus 15, GT-2000

Bottom line: A number of performance sneakers feature padding in the heel area, but the custom fit provided by Asics Personalized Heel Fit is in a class of its own.

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