NGK R5671A-10 Spark Plug for Sprint 410 Racing Engines, Set of 8

Ideal for Sprint racing applications Core is made from copper and has a nickel alloy tip Spark plus reach is .75" and has a 14mm thread pitch Specially designed for aluminum heads flat seat 14mm .708 reach Engineered to withstand severe mechanical and thermal shock associated with these high-revving, high-compression race crate engines