Original Donegan OptiVISOR Head Magnifier DA-10, 3.5X, Jewelers, Watchmaker Tool Optical glass prismatic lenses: Ground and polished to precision optical standardsbevel edged and mounted in an interchangeable plastic frame It tilts: Adjustable pivots allow the visor to be tilted out of the way when not needed and at your fingertips when you need magnification Adjustable headband: Conforms to fit all head sizesfabricated from a special blend lightweight material. Comfortable when worn for long periods of time. High impact visor: Provides a tough, durable, always-new appearance Genuine leather comfort band: Padded orthopedic felt adds to comfort