Size guide The Sienna Tank has skinny straps that meet in a Y at the back, so it stays out of the way while you move and looks just as good with jeans after. The cut is semi-fitted and a touch longer, skimming the body without clinging, and it has a built in bra with removable cups for light support without the extra layer (pop the cups out if you prefer). Made from our insanely soft signature Tencel fabric, it lets your skin breathe and keeps you cool through anything from hot yoga to brunch. Our fabrics are safe and BPA free. We're dedicated to using a nontoxic tree-based fabric that's grown in a clean and regenerative way. Composition is 92% TENCEL™ Lyocell/8% ROICA™ V550 spandex. Fit Details: The Sienna Tank is semi-fitted, skims the body, and runs true to size. Built in bra with removable cups. Care Instructions: Machine wash cold with like colors on the delicate cycle. Hang to dry.