The Wahl Lithium Ion Pen Trimmer will trim anywhere with incredible precision. This trimmer removes unwanted hair without nicking or pulling includes 3 interchangeable heads: detail trimmer， ear/nose and reciprocation trimmer heads. Easily touch up beards and necklines with the detail trimmer head，add the included guide comb to shape and trim eyebrows. Use the Ear/Nose trimmer head for hygienic grooming of ear and nose hair. The reciprocating head is great for fine detail trimming of eyebrow and beard hair. Also included in the kit is a lithium aaa battery for 3 hour runtime.