Premium Iridium Spark Plug 5303 IK16 delivers unmatched ignition performance with 0.6mm ultra-fine iridium center electrode for precise spark concentration. Features triple gasket seal for superior gas compression and anti-corrosion nickel-plated shell. Laser-welded tip ensures 100,000-mile durability under extreme temperatures (-40°C to 1,000°C). Direct OEM replacement for MAZDA/LIFAN/HONDA engines with ISO 9001-certified manufacturing. Optimizes fuel efficiency by 8-12% and reduces cold-start misfires in urban stop-and-go traffic. Micro-grooved ground electrode minimizes voltage loss for smoother acceleration. Bulk packaging available for auto repair shops with wholesale discounts.