DENSO W20ESR-U Standard U-Groove Resistor Spark Plug

The DENSO W20ESR-U (Stock #3057) is a high-quality standard resistor spark plug featuring DENSO's patented U-Groove ground electrode technology. This innovative design creates a larger spark nucleus at the point of ignition, delivering superior flame travel for more complete and efficient combustion compared to conventional spark plugs.

Key Features:

• Patented U-Groove ground electrode produces a larger, hotter spark for improved ignitability
• Copper core center electrode provides superior thermal conductivity and heat dissipation
• Built-in resistor reduces electromagnetic interference with vehicle electronics
• 14mm thread diameter with 19mm (3/4") reach and gasket seat design
• 13/16" (20.6mm) hex size for easy installation
• 5-rib insulator made from purified alumina powder prevents flashover and voltage loss
• Machine-rolled threads reduce cross-threading and seizing in aluminum heads
• 360-degree laser-welded construction ensures durability
• Removable terminal nut for flexible installation
• Heat range: 20

DENSO U-Groove spark plugs are engineered to deliver improved fuel efficiency, enhanced throttle response, and lower emissions. Each plug is 100% pre-fired at the factory to ensure reliable operation right out of the box. As original equipment in many automotive applications, DENSO plugs are manufactured to strict OE standards or above, offering performance that lasts up to twice as long as conventional spark plugs.