THIS MODEL IS A 1.75 MAGNIFICATION WITH A 14 INCH WORKING DISTANCE - Attaches to eyewear by way of wire locking device. A great choice when you leave the magnifier attached to your glasses. The working distance of each magnifier varies based on the strength. The following represents the working distance for other models: 1.50X (712) has a working distance is 20 inches 2.00X (714) has a working distance is 10 inches 2.25X (715) has a working distance is 8 inches 2.75X (717) has a working distance is 6 inches 3.50X (710) has a working distance is 4 inches last digit of model # = dioptor ex: 717=7 dioptor is curve of lens not power, curve results in power.