GENUINE LEATHER SURFACE - Utilizing top-grain chrome-tanned leather to provide a pleasant touch, each leather piece is precision-cut, molded in, and hand-trimmed to perfection. EXQUISITE CRAFTMANSHIP - Immaculate attention to every detail - Genuine leather top cover, textured aluminum wheel and alloy frame with precision bolts. TRACKS Virtually ANYWHERE - The PixArt PAW3805 sensor is designed to track flawlessly on virtually any surface, including glass and other high-gloss materials. DUAL USB-RF & BLUETOOTH - Interfaces Connect wirelessly with Bluetooth or RF via USB receiver. Works on Bluetooth enabled PC's natively but also includes a USB RF receiver for computers without Bluetooth. LONG USAGE TIME - Built-in is a high-capacity 1000mAh Lithium Ion rechargeable battery. Usage time is up to 4 months on a single charge.