Secured wireless connection – Microsoft 2.4 GHz wireless delivers a secured and reliable connection with up to a 15-foot range. Easy-access hot keys – Quickly access Calculator, volume controls, mute, and play/pause. Microsoft Optical Technology – 1000 dpi provides responsive cursor control. Snap-in transceiver – Stows conveniently under the mouse. Optimized power management – Power management system extends battery life.