The portable 15 inch Pace Clock is battery operated using one "AA" battery and has a one-piece pedestal design. It has the same design features of the 31 Pace Clock including the octagonal shaped housing, which is designed for optimum visibility at great distances. The sweep minute and second hands are designed to resist warping and damage. A clear plexiglass lens protects the face and hands from splashing and weather. Large numerals make this an ideal tool for aerobics and personal training.