NGK Spark Plug Stock # 7401

The NGK Spark Plug Stock # 7401 is a premium iridium-enhanced ignition component engineered for reliable cold-start performance and extended service life in demanding combustion environments. Built on NGK's proven resistor-type architecture, this spark plug delivers dependable firing consistency across a broad range of engine loads and RPM ranges. Whether you're maintaining fleet equipment, restoring vintage machinery, or optimizing OEM-spec ignition systems, the NGK UR4IX offers the precision fit and proven durability that professionals demand.

This NGK iridium spark plug features a 14 mm thread diameter with a 0.460 inch reach and tapered seat design, ensuring secure, gas-tight installation in standard spark plug wells. The iridium-enhanced electrode geometry concentrates electrical energy for rapid, complete combustion initiation, while the resistor core suppresses electromagnetic noise that can interfere with sensitive engine management and audio systems. The compact 1 x 0.9 x 3.4 inch profile and 0.09 lb weight make it a lightweight, space-efficient solution for virtually any small-displacement to mid-range automotive or power equipment application requiring NGK OEM-equivalent performance.

Technicians and vehicle owners working with engines specified for 14 mm spark plug configurations will find the NGK UR4IX an ideal direct replacement for worn or fouled plugs. Its tapered seat design eliminates the need for a gasket, simplifying installation and reducing the risk of improper seating. The resistor-type construction makes it particularly suitable for motorcycles, small engines, portable generators, and classic automobiles where EMI suppression is critical. Installation requires only basic hand tools and a spark plug socket—no special equipment or technical expertise needed.