The Supertech black-nitrided exhaust valve for Honda D16A1 is a +0.5mm oversize single replacement supplied individually. The part matches the +0.5mm oversize and nitrided finish described, intended to serve as a like-for-like exhaust valve replacement for the D16A1 engine application when an oversize exhaust valve is needed.
Supertech Honda D16A1 Black Nitrided Exhaust Valve - +0.5mm Oversize - Single