Carefully researched design has resulted in new optical acrylic lenses with a maintenance-free sealed LED light source and easy to replace battery compartment. Outstanding light, extended battery life, and aspheric, abrasion resistant lenses make these exceptional hand-held magnifiers for daily reading activities. They take 2 C batteries, not included. The complete magnifier (head and handle) can be purchased and more powerful heads can be added later, as they are needed. Lens measures 1.7".