Mermaid Maternity rash guard swim shirts offer extra coverage for comfort, modesty and sun protection. Our exclusive drawstring hem ensures that it won't float up when you're in the water. This rash guard swim shirt does not have built in bust support. It is designed to be worn over a bikini top or sports bra; perfect for women who want the support of a bikini or bra but also want more coverage. Pair it with our coordinating Mermaid Maternity swim short, swim skirt, or swim brief (each sold separately) for a cute, sporty look. Hand wash. Air dry. Made in USA. Midnight Glow is 86% Polyester, 14% Spandex; Polka Dot is 80% nylon; 20% spandex. For a fitted look, order your pre-pregnancy size. For a relaxed fit, order one size up. Pre-pregnancy size 4-6 is size small, 8-10 is medium, 12-14 is large, 16-18 is XL, 20 is XXL. Also, consider your current bust measurement (measuring around the fullest part of your bust). Our size small best accommodates a bust measurement of 36-37.5 inches. For size medium, bust measurement is 38-40 inches. For size large, bust measurement is 40.5-42.5 inches. For size XL, bust measurement is 43-45 inches. For size XXL, bust measurement is 46-48 inches. If you have specific fit questions feel free to contact us.