I have experienced no issues with this product in my usage environment. I used it right up until listing it, and there were no problems with scratching. However, please understand that this product is over 15 years old before purchasing. (There is a possibility of issues arising in the buyer's usage environment, and it could malfunction at any time.) Unfortunately, in the past, I have received unfair claims and had to deal with them because the above points were not understood. *Therefore, please only purchase if you understand that the transaction is based on no claims and no returns. Due to the nature of the product, if you cannot understand the above, we recommend purchasing a new product with a manufacturer's warranty.