Mopar Hemi 6.4 Rocker Shaft Stabilizers and Collars, complete set. These 6.4 Stabilizers and Collars will virtually elimate the possibility of rocker shaft and rocker arm failure on Gen 3 6.4 Heads, including Appache, Eagel, thitech and Edelbrock Heads. These Stabilizers and Collars are CNC Machined from Aircraft Aluminum, and anodized for long last appearance and wear.