Fixes or prevents open tray error & DVDs or games that dont play, load slowly, skip or freeze during playback ; Cleaning the laser lens can extend the life of the DVD player, while improving image & sound quality ; Exclusive 10-brush Cyclone Clean process will remove dust, dirt & debris from the laser lens ; Includes home theater sound calibration tools to help maintain ideal audio playback settings, with on-screen & voice instructions available in Eng, Sp & Fr ; Also safe on Xbox(R) & computer disc drives;