Set of 4 Genuine Honda intake valve guide for the CB500 and CB550. If you're doing the top end or replacing the valves, it's a good idea to replace the valve guides while you're in there. There are 4 per bike.
Honda part number: 12023-465-405, 12021-323-300
Fits Honda:
CB500K - 1971-1973
CB550K - 1974-1978
CB550F - 1975-1977