Undershirt of Underfit has achieved an immense popularity in the US. Unlike most of the undershirts, it stays completely tucked in properly throughout the day. The design of this type of shirt is specially made in a way so that you won't have to worry about annoying re-tucking. I am Chris Walker, and I love this inner shirt for regular use. You can avail more information about this shirt from their official website, and you can get additional details from their Facebook, Twitter and Linkedin account. Underfit is also available in CrunchBase.