New for 2008. The Performance Engi Sleeveless utilizes a 3D knitted fabric with body mapping for precise body temperature regulation and moisture control. A full front zipper and ventilation panels at key sweat zones provide additional temperature control. Minimal seams for ideal comfort, a signature close to the body fit, three rear pockets with a 4th zippered, silicon waist gripper at bottom back. MP3 wire port in back pocket.