DRIFIRE is one of three of my favorite underwear options for arc flash rated safety garments. They have a special 33% off.
I wear these t-shirts a lot and love them. There are only a few on the market I like and this is one of them.
I also like Pyrosafe by Antex, PerformanceWear by Gehring, Indura Ultrasoft by Westex and a new material coming out by ITI.