I bought the Tri Singlet to support my back and shoulders while doing office work, so I consider it an ergonomic aid.The XL is perfect for my needs, although I wear L clothing otherwise (hence only four stars). The zipper makes it easy to put on and off, the built-in shelf bra is surprisingly effective, and the shape is perfect. Since it was on sale I got a turquoise/gray color I don''t usually wear, but it''s very attractive and a good alternative to black or while. It did not shrink or bleed when washed, which was a real surprise. I''ve worn it for many hours now, and my muscles don''t tire as soon.  I am completely sold on the quality of this product!