I'm not normally a big fan of thermal mainly because it's either underwear or a sweatshirt. It's hard to find a thermal shirt that is as good as an extra layer as it is an awesome looking shirt. Smart Guy is just that; a perfect anytime shirt that adds a new dimension to boring business casual. Dare to wear it with a pair of slacks as easy as you would a pair of jeans. Smart Guy is also perfect with shorts and Rainbow Sandals.