This portable set features Welch Allyn's finest diagnostic instruments. The 11730 3.5V Coaxial Ophthalmoscope Head features precision optic with 68 lenses in single-diopter steps (+38 to -30). Halogen lamp illumination insures true tissue color and a Polarizing filter virtually eliminates corneal reflection. The MacroView Otoscope (23820) uses Halogen HPX lamp and fiber optics for cool light with no reflections, no obstruction. It comes with a built-in throat illuminator/penlight and a wide-angle viewing lens for instrumentation under magnification. The 3.5V Nasal Illuminator from Welch Allyn (26535) is three instruments in one. It facilitates easy nasal examinations with halogen HPX illumination for true tissue color and a reusable tip. As a bonus, the head can be detached to use the illuminator as a throat illuminator or penlight. The Welch Allyn Lithium-Ion (Smart) Handle (71900) is just half the weight of current 3.5v handles. It averages 120 minutes of on time between charging. It has the smallest diameter of any 3.5v power handle on the market. The textured handle is made of sturdy resin. It comes with a low-battery indicator and lithium-ion battery technology that has no "memory" effect. It has a soft-grip rheostat intensity control, and AC charging module with retractable prongs that is easily removable from the handle.