Brisk RR15YC-1 Super Racing spark plug for race car engines. Features a 14mm thread, 25mm (1in) reach, and 16mm (5/8in) hex with a tapered seat. Heat Range 15, resistor, with a copper core electrode for improved heat dissipation and ignition in high-performance racing engines. Ideal for turbo or nitrous setups. Recommended torque: 15-22 ft-lbs. Gap: 0.020-0.035 inches. Sold as each.