Specifications:Weight: Approximately 8 oz. 210 gr.Overall length is 4"Insertable depth is 3-1/2"and has two "bumps", each 1-3/8" (35mm) in diameter. Top smaller electrode is 1-1/4" in length and the ridge is 1" at the lowest point. Bottom larger electrode is also 1-1/4 in diameter but 1-3/8" in length. The bottom neck is 3/4 in diameter and 3/4" long. The base is 1-3/4" in diameter and 3/8" thick. Two 3/16" diameter holes have been placed on each side of the base to that it could be fastened to a flat surface or secured inside or on a belt. There is also a channel grooved into the bottom of the base for the electrical wire to lay into for out of the way flat surface fastening.