Thank you for viewing. Features: This is a women's open-back kneeskin for masters swimmers who swim every day. It uses "FLEX Σ χ (Flex Sigma Kai)", an environmentally friendly material made from recycled polyester yarn, which reuses plastic bottles. High elasticity supports all movements in the water. Excellent water repellency keeps it lightweight. Furthermore, the fit created by the three-dimensional design and cutting prevents water from entering and provides comfortable swimming. WORLD AQUATICS approved / FINA approved It has hook-and-eye loops that can be used with separately sold cups (※Cups are not included).