Material: 55% Polyester, 40% Rayon, 5% Spandex. These are the same premium material as our previous "loose fit perfect tees" but with a different fit. Fit: These are not the same style of "loose fit perfect tees" we had previously as these are cut straight across at the bottom and more fitted. We suggest sizing up one size. Since these are more fitted, they may work better for cardigans, tucking etc. As a size 6 and typically a S/M, I would prefer a medium.