ELECOM Wireless Mobile Trackball Model Number: M-MT1DRSBK 《For purchases made by August 20th (Wednesday), we will ship on the same day.》 This is a small trackball mouse. Both the mouse and the ball have no scratches and operate smoothly. The artificial ruby surrounding the support ball is also clean. Since batteries are also included, you can use it immediately by plugging the receiver into your computer. Recommended as a first trackball. Size Width 73.7mm × Depth 89.9mm × Height 41.3mm Feel free to comment if you would like additional product images or have any questions.