TENMOS T5 Wireless Rechargeable Mouse USB Optical Ultra Thin Mini Computer Silent Mouse for Mac/Notebook/Laptop (blue) RECHARGEABLE: Built-in rechargeable battery.No need to change batteries. Up to 18 months of Li-ion battery life virtually eliminates the need to change batteries (Battery life may vary based on user and computing conditions.)Make sure to turn on the mouse when you charge it. SILENT CLICK: Special soundless design for the right and left buttons, you can use it in your office to build a quiet office atmosphere. ADJUSTABLE DPI: 600/1000/1600/2400 DPI free switch. Dots per inch (DPI) is a measurement of how sensitive a mouse is. The higher DPI, the farther the cursor on your screen will move when you move the mouse. COMFORTABLE TO USE: suitable for both right and left handed. Up to 10m transmission distance. EASY INSTALLATION: No additional software is required. Simply 'plug and play'.