National Safety Apparel FR Control 2.0 Long Sleeve T-Shirt in Desert Sand FR 5.5 oz. Mod acrylic Blend Unique base layer actively regulates body temperature, reduces perspiration & limits overheating, and is Anti-Microbial to reduce odors. Stretch fit (Arc Rating=4.0 cal/cm) HRC 1 NFPA 70E Compliant; Meets OSHA 1910.269