features: - 60°degree angle unique design, Ergonomic vertical mouse MV20 2.4GHz wireless optical sensor,Max support 10 meters stable connect. - 3 Levels Adjustable DPI,one key switching Buttons: Left/Right, Forward/Backward, DPI, Scroll Wheel(middle button) Wireless Version Resolution: 600-1200-1600 DPI Adjustable - High-end Surfree invisible engine Surfree invisible engine makes your mouse move freely on almost all surfaces. - 9-month battery life With Rapoo's latest energy saving technology and power switch, you can use your mouse without power interruption for up to 9 months. - System Requirements: Windows XP/vista/7,Windows 8/10,with USB port.