Classroom fluorescent lights can be strong! These heat-resistant Flourescent Light Filters reduce glare and flickering to create a calming learning or work environment. Filters are flame retardant and attach to standard ceiling fluorescent light fixtures with super-strong, built-in magnets that keep filters in position. The package of 2 blue patterned light filters includes a Certificate of Conformance for flame retardancy. Filters measure 4'long X 2' wide each.