Under Armour Men's UA Spine Clutch Running Shoes Synthetic UA ClutchFit technology wraps your foot with a lightweight second skin for powerful support & incredible feel Ultra-breathable mesh with a second layer of synthetic underlays, for locked-in midfoot support Die cut 4D Foam footbed conforms to your foot's exact shape, eliminating slippage UA Spine chassis technology creates an incredibly light, flexible feel without sacrificing support Micro G foam encapsulated within the chassis delivers unrivaled rebound & energy return