I bought this for my daughter buoy 18 months and almost 10 kg because there is nothing for children under 11kg on the market. Pool tested with great success. Sweetie beats in feet and loves it. I am very surprised to see comments like what the buoy turns, because given the child's position (mine) it seems impossible ... Very reassuring, a bit long to put on and adjust perhaps the first once but great product. Like a fish in water ^ _ ^