The Apple Watch Series 3 with a gray sport band combines the elegance of a dress watch with the utility of a sports watch. The space gray aluminum case measures 42 millimeters, with a fluoroelastomer band to withstand the rigors of exercise. Easily charge the watch with wireless charging technology. Its cellular connectivity also conveys all your most important notifications. Thanks to the internal gyroscope and altimeter, you can use advanced features to measure motion.