This is ANSI Class 3 Compliant. Made with lightweight 4.1 oz Birdseye Knit Polyester. It feels butter soft on the inside, yet is work-wear durable. It features a rib knit collar and 3-buttoned placket for a professional appearance The performance fabric wicks away moisture 3 times faster than cotton. Our High Visibility Shirt is compliant to ANSI/ISEA Class 3 for increased conspicuity. In addition, this shirt features ANSI/ISEA 107-2020 Reflective Material durable through 50 home washes.