The 4-way Privacy Filter for ThinkPad 10 utilises the patented 3M microlouvre privacy technology to dim the screen and block the vision of wandering eyes from four directions: above and below the tablet, and from both sides. It also guards your screen from scratches and smears.The 4-way Privacy Filter for ThinkPad 10 utilises the patented 3M microlouvre privacy technology to dim the screen and block the vision of wandering eyes from four directions: above and below the tablet, and from both sides. It also guards your screen from scratches and smears.