10 Best Tank Tops With Built In Bras For Every Occasion Transcend Built In Bra Tank Athleta Transcend Built In Bra Tank Athleta 10 Best Tank Tops With Built In Bras For Every Occasion. Material:?? 91% Viscose, 9% Spandex?? (Viscose has a nice feel and shine, similar to cotton. It offers excellent moisture absorption and breathability due to its chemical similarity to cotton.) Key Features: Removable Padding With Elastic Underbust Band Ultra light, breathable material Comfortable, secure fit for any activity Stylish design that blends function and fashion