The Welch Allyn 2.5v PocketScope Otoscope with Throat Illuminator uses halogen light for true tissue color and consistent, long-lasting illumination. Its fiber optics provide cool light with no reflection, no obstruction. The wide angle viewing lens allows instrumentation under magnification. It has a sealed system for pneumatic otoscopy. Detach the head to use the built-in throat illumination/penlight for added versatility. The 22820 comes with a AA-Battery powered handle and two AA batteries.