【1】 The scientific ergonomic design encourages a healthy and neutral "handshake" handle and arm position to achieve smoother movement and less overall stress. 【2】 The optical tracking technology with 800/1200/1600 DPI resolution provides higher sensitivity than standard optical mice, enabling smooth and accurate tracking on various surfaces. 【3】 Added next/previous buttons to facilitate web browsing; the best choice for Internet surfers, gamers, and those who work in front of the computer for a long time. 【4】 After 8 minutes of inactivity, it enters power-saving mode (power is completely off), press the left and right buttons to wake up. 【5】 The package includes: 1 wireless vertical ergonomic optical mouse (excluding 2 AAA batteries), 1 2.4G USB receiver (at the bottom of the mouse), and 1 instruction manual.