Pre-unit 6T T110 and T120 Plasma hardened UK made Exhaust valve and Unit 650cc up to 1966
Valve is hardened using the "Pulsed Plasma Nitriding." process, this gives the valve resistance to wear and anti friction properties , when this type of valve is matched with our Colsibro material valve guides , you have the best combination for valve and guide, for performance and longevity
