Crane's locknuts for stamped steel rocker arms are available in self-locking type standard configurations, and in our patented Kool Nut oil deflection design. These direct the pressure-fed oil flow to the pivot ball-rocker arm interface, resulting in superior lubrication and cooling in this critical area. Review products and applications. Rocker Arm Kool Nuts Set/16 99768-16$48.00 Rocker Arm Kool Nuts Set/16 99769-16$48.00 Self Locking Rocker Arm Nuts Set/16 99770-16$15.00 Self Locking Rocker Arm Nuts Set/16 99771-16$19.36 Self Locking Rocker Arm Nuts Set/16 99772-16$24.00