I don’t know much about these but I do know that the middle piece is much larger than normal which I guess means I can handle much more current proximately 2“ x 2“ is the middle section the overall length is pictured it is approximately 6 1/4 inches and the entire piece is approximately 2.75 inches wide. Inside the tube is uranium glass at the top and bottom used to conduct scientific experiments with current. Very cool item to have in your collection instead of the same old boring Uranium sherbet cups and plates like most people have.