Under Armour Men's UA Speedform&Acirc;&iquest; Apollo Synthetic-and-mesh Seamless Heel Cup - With silicone grip for the perfect fit. Slimmer Athletic Cut - Results in eliminated bulk and therefore more efficiency. Smooth Seams - So that you can run uninterrupted and without irritation. Light, Flexible Material - Fits your foot exactly. Micro G Midsole - Provides superior comfort and support.