Blackout Privacy Filter is designed for 19" LCD monitors to prevent unauthorized viewing. Filter helps ensure the privacy of on-screen data on your LCD monitor. Microlouver technology creates a narrow viewing angle so the image is only visible to those directly in front of the screen. Side view is black. Filter protects delicate LCD surface from damage while eliminating glare and increasing contrast. Filter features overlay LCD surface for a built-in look. The interior dimensions are 11-7/8" width and 14-3/16" height.