My four-year-old broke her arm on the first day of summer, and we were so bummed. My neighbor bought us the Bloccs protector, and I have to admit, I was very skeptical at first. We tried playing in the backyard sprinkler first, and it kept it totally dry. So we decided to try the pool, and it was amazing! The protector totally sealed on her arm and kept her cast completely dry so she could enjoy summer!