Rocker Shaft Washer - M14-P, BAG OF 6
Controls rocker end play on each rocker shaft.
4 required per cylinder, 36 per engine.
Familiarize yourself with a good technique for removing the rocker arm. There are very many roller bearings within the rocker arm that want to escape.
Just one is enough to ruin your day.
Caution is advised.
In other respects, these washers very easy to replace, and one of the 'usual suspects' when a new Rocker cover O ring did not solve leaks going backward onto the exhaust system.