This framed filter uses optical-quality glass to lessen eyestrain. Anti-reflection coating helps reduce up to 90% of screen glare. Includes a ground wire to lessen static charge while minimizing dust build-up. Meets American Optometric Association (AOA) specifications for VDT glare reduction. CRT Monitor Size Range: 19.00 in - 21.00 in; Maxiumum LCD Monitor Size Range: 20.00 in.