Baseball Caps by Flexfit. Details:Flexfit has been a trusted name in headwear for nearly 20 years, which is why the hat pros have teamed up to offer this best-selling style baseball cap. The one-size-fits-all thp Flexfit hat cotton twill cap from the hat pros is constructed with yaupon's patented technology, and is made of 98% cotton/2% spandex to allow for an incredibly comfortable cap. Additionally, a specialized spandex material is weaved throughout the sweatband and crown of the hat for genuine Flexfit comfort.