From George & Ginger:
The Switch It Up Bra Back Edition is an all-in-one design that's perfect for mixing and matching your favorite styles! One basic, full coverage front with TEN different back options - all interchangeable and ready to be customized just for you!
Recommended Fabric: 4-way knit with at least 50% stretch, such as cotton lycra or athletic knit.
Sizes: Tweens 12-14 and XXS-5XL