NOTE:The connector/wireless receiver is found inside the back side of the mouse. Wireless operating distance: Approx 10m4. Sensor Resolution: 540 Trackball comfort: Sculpted shape supports your hand and stays in one place-move the cursor without moving your arm Work and play anywhere: Get smooth, precise cursor control wherever you use your trackball-your desk, couch, even your bed Logitech Unifying receiver: Connect up to six Unifying compatible devices with one tiny wireless.Long battery life: Go for up to 18 months without changing the included AA battery* (*Battery life may vary based on user and computing conditions) receiver that stays in your laptop.For Windows or Mac OS: Robust 2.4 GHz wireless connection lets you control your laptop, desktop computer or home theater PC wirelessly from up to 30 ft. away** (** Actual wireless range will vary with use, settings and environmental conditions) Please refer the User Manual before use. Compatible with Windows XP, Windows Vista, Windows 7, Windows 8, Windows 10 and Mac OS X 10.5 or later. Mac users will also need the software to enable the back, forward, and middle button functions The logitech wireless trackball m570 gives you a different kind of comfort. it stays in one place and supports your hand to let you work all day with ease.