These are the rocker arm shaft assemblies for 1955 - 1957 Cadillac. These will fit all 1955, 1956 & 1957 Cadillac's according to the parts book. If you are just looking to use them for parts, the rocker arms themselves fit 1955 - 1966, the support blocks where the head bolts go through only fit 1955 - 1957, and the shafts fit 1949 - 1957. The whole assembly together as shown though fits 1955 - 1957, please make sure they are correct for your application before buying them. These are in good used condition. I have cleaned and dis-assembled them to check them over, and there are no gouges, scrapes or rough spots in them, and no signs that there is anything wrong with them, just some normal wear on mechanical parts of this age. Good used original parts, could be used as is. Sold As Is, As Shown in pictures