Cross computer control: Game changing capacity to navigate seamlessly on 3 computers, and copy paste text, images, and files from 1 to the other using Logitech flow Dual connectivity: Use with upto 3 Windows or Mac computers via included Unifying receiver or Bluetooth Smart wireless technology Advanced ergonomic design: Perfectly sculpted, hand crafted shape supports your hand and wrist in a comfortable, natural position Auto shift scrolling: Speed adaptive scroll wheel auto shifts on the fly from click to click to hyper fast scrolling; Wireless operating distance: 10 m Battery: rechargeable Li-Po (500 mAh) battery. Rechargable battery: Upto 70 days of power on a single charge; Number of buttons: 7