Chattanooga Intelect™ Vacuum Electrodes comes in 3 sizes. Here are the sizes for Vacuum Electrodes, Vacuum Electrodes 30 mm (4) Stainless Steel, Vacuum Electrodes 60 mm (4) Stainless Steel and Vacuum Electrodes 90 mm (4) Stainless Steel. There are Four electrodes is a pack and these electrodes can be use with Chattanooga Intelect Vacuum Machines