The Supertech black-nitrided exhaust valve for Honda K20 and K24 engines is supplied individually as a single replacement valve. The nitrided finish noted in the product text indicates this valve is intended for exhaust-side service in the listed K-series engine applications and is sold as one valve for targeted replacement needs.
Supertech Honda K20/K24 Black Nitrided Exhaust Valve - Single (Drop Ship Only)