This is a trackball with a wrist rest. The item includes only the main unit; there is no outer box or instruction manual. Also, the storage environment is smoke-free and pet-free. By placing it under the keyboard, you can use your thumb to operate the trackball for mouse control, clicking, and right-clicking, which can improve work efficiency. Please refer to the product page below for product details. https://www.sanwa.co.jp/product/syohin?code=MA-TB42BK However, the height adjustment of this product did not work well with my favorite keyboard, so I purchased a separate keyboard with a trackball. Therefore, this item is almost unused. Operation has been confirmed on Windows 11 and MacOS (Sonoma).