A jockstrap (also known as a jock, jock strap, strap, supporter, or athletic supporter) is an undergarment designed for supporting the male genitalia during sports or other vigorous physical activity. A jockstrap consists of a waistband (usually elastic) with a support pouch for the genitalia and two elastic straps affixed to the base of the pouch and to the left and right sides of the waistband at the hip. The pouch, in some varieties, may be fitted with a pocket to hold an impact resistant cup to protect the testicles and/or the penis from injury.
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Jockstraps are fairly consistent in design with variations appearing in details like width of waistband and fabrics. Some jockstraps are designed for specific sports. Swim jocks, for example, have a narrow waistband and hockey jocks have adjustable elastic straps and garter clips that hold hockey socks in place while the bulky goalie protector has genital and abdominal foam padding. Windproof jockstraps have a special layer of fabric to protect the wearer from wind and cold in winter sports. Fashion jocks are manufactured in stylish designs with colorful fabrics.