This original, authentic Grenet Cell was a common item on Edison's work bench and used in a number of his early products. This one is the small size which is 8" high, 4" in diameter at the largest point of the globe. It also has two solid brass binding posts and a brass slide regulator rod. The Grenet cell works with two carbon plates and a single zinc plate which is extracted from the liquid electrolyte chemistry by lifting the brass regulator rod. This type of battery is a rare and valued item, a very fine part of early electric history.