I wore this once at the beach during a trip to Okinawa. I didn't go in the ocean or pool. It's a tankini type, so it was easy to put on my baby. As shown in image 6, it can be used without a diaper. I bought it for about ¥3500. The size is 6M, and it's for babies weighing 4.5-8 kg. I'm also selling an i play hat. I can sell them together if you'd like.