These are Chaco water shoes, suitable for both land and water. ※ These are not Keen. Size: 22.5 cm I bought these for trips to the pool and river with my children. Now that they've grown up, we don't go anymore, so I'm selling them. The single strap design is convenient, allowing for overall length adjustment. According to the store staff, these shoes are made by a company that builds boats and yachts, so they have high grip and won't slip on wet decks. I bought them because I was looking for shoes that wouldn't slip on moss in the river. I hope someone can use them! ^ ^ There's a little scuffing on the toe area, but overall, there's no major damage. Please check the photos. Instant purchase is OK. The following is a quote from the manufacturer: The barefoot-like fit and quick-drying engineered mesh upper are recommended for water activities. Chaco's uniquely developed innovative lug design provides high traction and grip, making it difficult to slip even on wet surfaces. The straps are connected in a single piece, and these shoes are perfect for summer activities, maintaining the signature Chaco fit.