I was really excited about getting these!!! I made sure to ask at what depth they would float as we have a deep Baja shelf. They stayed that would not float in anything under 18 inches. So after feeling reassured they would stay in place I was very disappointed!!! They float and my shelf is 15 inches deep. Hard to tell from pictures but the front legs float up and don’t touch the ledge at all which makes them move all over the place.  Bought these specifically for in pool use and made sure to ask question before purchase and still was a huge disappointment.