With your Logitech Performance Mouse MX, you've got the power to conquer almost any surface and any task without a second thought. With Logitech Darkfield Laser Tracking, you get accurate, precise cursor control on virtually any surface, even glass tables (4 mm minimum thickness) where optical and standard laser mice fail.With your Logitech Performance Mouse MX, you've got the power to conquer almost any surface and any task without a second thought. With Logitech Darkfield Laser Tracking, you get accurate, precise cursor control on virtually any surface, even glass tables (4 mm minimum thickness) where optical and standard laser mice fail.