Up for sale is a set of 12 Rocker arm adjusting screws with nuts. These screws have a spring in them to make engine run quiet. I believe they were made in 1946 by the box but they fit all the 216 235 & 261. The locking nuts are brand new and they have a 11/16 hex on them. The old ones should be 5/8.
Thread Dimension is 7/16-20
Total length is 1.356
Ball dimension is .345
1934 - 1962 Chevrolet 194, 216, 235 &261
If you have a question be sure to ask and maybe I can help you