NOT MADE IN CHINA SUPER HARD NON MAGNETIC EXHAUST VALVE AND STOCK TYPE INTAKE VALVE. ATC110's from 1979 TO 1983 TOOK THE SAME VALVES AS THE 90'S If you have an ATC110 1984 or 1985 this will not work. For some reason Honda changed the valve, valve COTTER and retainer midway through the 1984 year actually the engine serial numbers below/smaller THAN E2607160, in 1984 can use the same valve as an 83 or older. Another option for 1984(ENGINE #'S HIGHER THAN E2607160) and 1985 owners, would be to get the older valves retainers and valve Cotter's everything else is the same In all the 110 heads. THIS FITS MOST S90 CM91 340V/340W @ *VALVE_COTTOR CT90_ATC90_OTHERS (SOLD_EACH) 14781-001-010 7/20M (R2010)THESE ARE ALSO KNOWN AS KEEPERS. THEY ARE SOLD EA. THERE ARE 4 PER ENGINE. THESE FIT ALL ATC90'S, CT90'S AND ATC110'S THRU 83 . R2010 @ UPPER_VALVE SPRING_RETAINER FOR_5.5MM_VALVES (SOLD_EACH) (293C)THIS HOLDS THE VALVE COTTORS IN AND THE SPRING IN PLACE. FITS ALL Z50A'S CT70'S SL XL CL ATC TRX 70'S MOST ALL 50 AND 70 ENGINES and CT90 ATC90 (ATC110 TO EARLY 84) THAT HAVE A 5.5MM VALVE STEM 293C