This is ANSI Class 3 Compliant. Made with lightweight 4.1oz Birdseye Knit Polyester. It feels butter soft on the inside, yet is work-wear durable. The performance fabric wicks away moisture 3x faster than cotton and minimizes odor. Our High Visibility Shirt is compliant to ANSI/ISEA Class 3 for increased conspicuity. This shirt features 3M™ Scotchlite™ Reflective Material – 5510 Comfort Trim adds extra comfort and does not buckle or rub like sewn on reflective tape.