Penguin Pools offer you the best in Curved Kidney Vinyl Liner Pricing in WI & MN. The Curved Kidney inground swimming pool design this shape is made to look like a kidney bean. It doesn’t have any straight walls and really gives your backyard some good character. A yard with a curved kidney swimming pool doesn’t have to worry about looking “plain”. We offer a variety of Curved Kidney pool dimensions for you to choose from, and customization is always encouraged.