New. Opti Visor Glass Lens. This is a new. Opti Visor lens. This is a precision instrument that improves vision and will increase your efficiency. Each lens is polished to precision opthalmic standards. It has an interchangeable lens plate for various applications. It is used for your. Opti Visor Binocular Magnifier. Great for jewelers, hobbies, sewing, artists, draftsmen, architects, pharmacies, doctors and more. The magnification is 3.5X. The focal length is 4" (102 mm).