10mm threaded. 19mm (3/4") reach. Used with a 16mm spark plug socket. Copper-core center electrode. NGK copper core V-Power spark plugs feature a specially designed v-groove center electrode, improving ignitability and reducing quenching. The 98% pure copper core delivers increased heat dissipation for more reliable starts and reduced risk of overheating. - Cold-rolled threads prevent cross-threading and damage to cylinder heads. - Trivalent plating eliminates need for anti-seize. - High-grade alumina silicate ceramic.
