NGK Part# R7437-9 Package Dimensions : 5.75" L x 3.2" W x 1.88" H Fine Wire Iridium Tipped Center Electrode Part number: 4654 Fine wire racing plugs are designed to give you a stronger spark from your existing ignition system. Slightly recessed fine wire iridium center electrode requires less voltage to ionize(jump) the plug gap. This allows a stronger spark which will better ig