Circular Knit is the most suitable knit structure for Compression wear with a 360 degree stretch compression. Exclusive to 2XU. 50 Denier Lycra, compared with 30/40 Denier used by our competitors. Denier represents the thickness of the yarn. A thicker yarn delivers a stronger compressive power. The main benefits of the unisex short is to aid blood flow towards the heart and also give extra support to the quadriceps, hamstring and posterior thigh muscle groups. Gives equal support so the fabric can compress the whole region of the upper legs - a key area of overuse and repetitive stress injury.