Microsoft Arc Touch Mouse Curve for comfort, flatten to pack. A perfect fit for your hand and your mobile lifestyle. Curve to turn on. Flatten to turn off. No button to switch. A green light flashes to show the battery is working, and then turns off to save battery life. Click. Tap. Flick. Control. Quickly brush up or down with your finger to flick into hyperfast scrolling. Take advantage of BlueTrack Technology, which combines the power of optical with the precision of laser for remarkable tracking on virtually any surface.1 Nano transceiver magnetically attaches to the bottom of the mouse for wireless freedom.