ClubSwim Solid Thin Strap One Piece Swimsuit in Black - it's a size 28 and is NWOT. I'm unsure as to the size conversion but it may be a Girls' 10/12 but can't be too sure. The ClubSwim Solid Thin Strap One Piece Swimsuit is perfect for all kinds of training, competition, water aerobics and fitness swimming, this long-lasting one-piece suit offers the comfort and fit you've been looking for. Round neckline V back Made without heavy-metal additives Thin straps reduce tan lines Large keyhole opening Full chest coverage under arms Fully lined front and back Flat-locked seams Seams lay flatter and closer to the body Comfortable fit Won't chafe against skin Cut to sit low on hips for greater rear coverage Long-lasting color retention Fabric: 82% Polyester, 18% Spandex Lining: 100% Sun Protection: UPF 50+ Back Style: V back Cup Support: No Bottom Coverage: Moderate Bust 11.5" flat Total length 23.5" #326