The 3M ThinkPad X240 Series Touch Privacy Filter and Lenovo 23.0W 16:9 Privacy Filter by 3M utilize the patented 3M microlouver privacy technology so only persons directly in front of the display can clearly see the image on screen. Passersby, or those viewing from an angle see only a blank, dark screen. With identity theft concerns growing and information disclosure laws becoming increasingly more restrictive, the requirement to protect sensitive data is critical. Unique attachment system keeps the security filter in place even when the laptop is closed.Reversible for either glossy or matte screen finish Reduces glare when used with the matte side facing you Easy on easy off attachment system Excellent for high traffic areas Helps protect your LCD panel from scratches 3M.