Familiar key shape and feel, whisper-quite. 3 tilt position, spill resistant design. Contoured mouse with soft rubber grips. Full-size and ambidextrous. Advanced optical tracking with 3 buttons and scroll wheel. Tiny Logitech Unifying receiver is so small it stays in your PC or laptop. Uses 3 "AA" batteries. Up to 36 months of battery life for the keyboard and 18 months for the mouse. English.