The Cotton Winter Mock is a new addition to 5.11's line of tactical clothing and sports updated fit, fabric and overall function. The fabric is a medium weight 95% combed cotton, 5% spandex with an enzyme washed finish which provides a soft, comfortable hand. The knit construction and spandex provide great flexibility and maximum range of motion. The new base layer fit keeps warm air trapped close to your skin and also enables the shirt to stay neatly tucked into your pants. We have re-engineered the fit around the neck providing a clean, professional appearance. For those of you who love the soft feel of cotton, The Cotton Winter Mock is the perfect thermal layering choice for wear under body armor, or 5.11's great selection of outerwear.