Here is a hard to find set of Jesel J2K rocker shaft ends with the larger 3/8" stud size designed for Ford Yates C3 cylinder heads. These shaft ends were used with Jesel J2K bar stands that were modified by Roush Racing to use the larger 3/8" studs in place of the smaller 5/16" studs. This modification was part of the restrictor plate engine program. The larger stud size was used in the restrictor plates because durability and rocker movement with the smaller stud at high RPM was a concern. If you have a set of Jesel J2K rocker stands with the 3/8" studs for, then these are the shaft ends you need to convert your 5/16" stud size rockers to work with your stands. there are 16 pieces, enough to convert a full set of rockers. Simply press apart the shafts on your rockers and replace the same end with these ends. These are used parts in top shape that came directly from Roush Racing. These are very hard to find and we have a very limited supply.