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 is a great option when the weather turns cooler or when extra sun protection is desired. The performance fabric wicks away moisture 3 times faster than cotton. Our High Visibility Shirt is compliant to ANSI/ISEA Class III 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.