✅《OPTICAL TRACKING TECHNOLOGY》The ELEOM trackball provides precise cursor movement for superior accuracy so you can get where you want on the screen quickly with less hand movement, improving productivity and efficiency. ✅《FUNCTIONAL 5 BUTTONS》Even this is compact-size, it comes with 5 physical buttons on the device. It is very easy to move in any direction. Also this mouse provides noise reduction on the click sound. ✅《DPI CURSOR》Designed with a high-performance gaming optics system sensor and lens. The DPI button can easily change between 750(LOW) and 1500(HIGH) DPI, making the movements of your cursor faster or slower. ✅《EASY MAINTENANCE》The ball rolls on three 2.5 mm large artificial ruby ball bearings. They are extremely smooth and the relatively large size prevents dust and dirt from clogging them. So you don’t have to clean the ball bearings too often. The ball is held in place by the ball bearings, but can easily be popped out of the device, by pushing it through the hole in the bottom and it can be easily cleaned. ✅《PRODUCT DETAILS》System requirements: Windows 7, Windows 8.1, Windows RT8.1, Windows 10 or later, macOS 10.14 or later, Size: W2.9\"(73.7mm) X L3.5\"(89.9mm) X H1.6\"(41.3mm), Weight: 2.7oz(without battery), DPI: 750/1500 count (switchable), Connectivity: wireless, 1 X AAA battery(Included), Mouse semi-hard case Includes