DESC: 3.5V Coaxial Ophthalmoscope with patented coaxial optics offering a greater field of view, shadow free spot, and easier entry into the patient's pupil. Special polarizing filter reduces corneal reflection by 99%. 3.5V Diagnostic Otoscope also has built in throat illuminator - two in one instrument! Features fiber optics for a cool light with no reflections or obstructions, plus a wide angle viewing lens for instrumentation under magnification. 3.5V Direct plug in handle, with chrome-plated brass knurled finish, features a long-lasting rechargeable NiCad battery. Handle accepts all Welch Allyn 3.5V heads.