The Power Compression Short With Bioflex Cup is made with 4-way stretch, moisture-wicking fabric. The Power Compression Short With Bioflex Cup also features a a unique wraparound X-FIT cup retention system with an included BioFlex cup. The BioFlex Cup is made of flexible, shock absorbing plastic and fits perfectly into the fully ventilated cup pocket. These shorts maximize both comfort and protection, making them a much better bargain than purchasing just sliding shorts or a protective cup sperarately.