Tired of hearing noisy tappets? This is because stock roller rockers are not adjustable (they are fixed).

Typically installation of fully adjuctable roller rockers include the following:
Purhcase fully adjustable roller rockers (between $200-400)
Machine the heads to accept 7/16 screw in stud ($between $100-150)
Purchase 7/16 rocker studs, Guideplates and hardend push rods (between 100 - 150)
All of which becomes an expensive exercise.

Finally Procomp Electronics came up with the solution! in which you can bolt on a set of roller rocker without all the hassle and machining .
Simply install the custom designed rocker studs and stainless steel roller rockers and fully adjust the lash and away you go.

Not to mention if you do choose to upgrade to Machining, studs and guideplates in futre you can simply remove the studs and use the roller rockers provided.