Jaco Hybrid Training Short - Silverlake-38 90% polyester Proprietary 4-Way Stretch and Wicking Fabric: Developed to provide the technical needs that are essential to high performance training; durability, exceptional 4-way stretch, breathability, moisture wicking and comfort Compression Waist-Tightening System: The patent-pending waist-tightening system utilizes a small compression panel that secures around the butt when the front drawstrings are tightened. The result is a loose look, but an incredibly secure and comfortable fit that is guaranteed to keep your shorts in place during the most strenuous of training regimens External Pockets: Lay-flat hook and loop closure pockets are found on the left leg and right hip Designed specifically to securely hold an iPhone, the right hip pocket is located at the optimal height for headphones to comfortably reach your ear