The distributor hole plug has a triple 'O' ring sealed design for a leak free installation. This plug has been engineered to be easy to install, it locks in place with a socket set screw and slotted shaft. No need for your distributor clamp, just slip it in and lock it down! A must have with all distributor-less/Crank Fired Ignition systems. Manufactured from 6061 bar stock with an anodized cap and CNC engraved CB Performance lettering.