I broke my leg and had to get a cast. The inside of the cast gets so sweaty and itchy, it's unbearable! I had heard it could drive you crazy, so I bought this in advance. It's a long stick with a bumpy end, designed to be inserted into the gaps in the cast for "scratching." There are cheaper metal sticks available, but this one is plastic, so it flexes, making it easier to reach the itchy spots. It's also great because you can insert a wet wipe into the hole and use it to wipe the area. I bought it, but since I didn't have a full cast, but rather a splint-like half-cast, I could take it off, so I didn't end up using it. I bought it on Amazon for 1190 yen.