The Lenovo 12.5W 3M Privacy Filter makes use of the patented 3M microlouver privacy technology, which allows only persons directly in front of the display to see the image on screen. Passersby or those viewing from an angle see only a blank, dark screen. This filter is excellent for high traffic areas. It also helps protect your computer's LCD panel from scratches. This Lenovo privacy filter also helps to reduce identity theft concerns. Also, with information disclosure laws becoming increasingly more restrictive, it is important to protect sensitive data. This laptop privacy filter fits 12.5" widescreen laptop computers with a 16:9 aspect ratio. It is reversible for either a glossy or matte screen finish