Our exclusive maternity rash guard swim shirts offer extra coverage for comfort, modesty and sun protection. The fast drying, stretchy fabric is SPF 50+ and contains Xtra Life Lycra, which that resists chlorine 5 times longer than regular spandex fabric. The drawstring bottom allows you to control the fit and also 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 shorts or swim skirt (each sold separately) for a cute, sporty look. nylon, Xtra Life Lycra. Hand wash. Air dry. For a fitted look, order your pre-pregnancy size. For a more relaxed fit, order one size up. Pre-pregnancy 4-6 is size small, 8-10 is medium, 12-14 is large, 16-18 is XL, 20 is XXL, and 22 is 2X. 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. For size 2X, bust measurement is 47-49 inches. If you have specific fit questions feel free to contact us.