From the manufacturer
G603 LIGHTSPEED Wireless Gaming Mouse
A revolution in wireless gaming, G603 combines our new HERO optical sensor and advanced LIGHTSPEED wireless to deliver class-leading performance faster than wired gaming mice and up to 10X the power efficiency.
Use Logitech Gaming Software to easily customize 6 programmable buttons for lightning fast DPI shifting, macros and more. LGS will also notify you when battery is low.