num+4 spark plug has unique revolutionary firing technology combining the advantages of surface air gap technology, nickel-yttrium four ground electrodes and a heat-fused center electrode with pure platinum providing optimum engine performance, smoother acceleration and top fuel efficiency.

• Revolutionary surface air gap firing technology featuring four yttrium-enhanced ground electrodes delivers the longest, most powerful spark for ultimate engine performance
• Four yttrium-enhanced ground electrodes provide optimum access to the air/fuel mixture for the most efficient combustion, plus the yttrium alloy ground electrodes reduce gap wear and oxidation for extended performance life
• Electrode gap is factory set to provide ease of installation – never requires adjustment
• Never requires gapping, the electrode gap is factory-set and never requires adjustment
• Provides ease of installation – never requires adjustment