The Jomar Pro-Model Stud Girdle is the best on the market today. The advantages of using a stud girdle include controlling “stud flex”, minimizing valve train harmonics and taking the load off individual stud bosses in the head. The net result is increased valve train reliability, especially when higher valve spring tensions and RPM are involved. The Jomar Rocker Arm Stud Girdle increases valve duration and lift in addition to stablizing the valve train.