THOMPSON TEEThe Thompson Tee Men's Sweatproof Undershirt | Crew Neck | Slim Fit | with Sweat Pads

Is it better to buy them a size smaller? Or do they fit well under other shirts? Also, are these more so just for armpit sweat?

What are the best care instructions for this shirt? My crews tend to end up with deodorant yellow stains even after a cold wash.

Is it against amazon policy to say that your product is made in the usa and it's really not?

What about customer reports of receiving Chinese knock-offs? Will I get the real deal?