The On Movement Sports Bra is all about comfort thanks to its elastic underband, open back design, sweatwicking mesh liner and premium, smooth fabric. Its moisture-wicking materials keep the sweat out so you can focus on your flow. The open back design increases both ventilation and freedom of movement. Soft lightweight materials combine to create a bra you'll want to wear all day. A gentle elastic underband keeps the bra in place while allowing free movement.