These Steel Super Lockswith lash cap recess feature a 10 degree lock angle and 3/8 inch valve stem size. They are recommended for all race applications because Super Lockshave a wider angle (10 degree) that better distributes the ever increasing valve spring loads over the retainer than typical 7 degree locks. Precision-machined out of super-tough, fatigue-resistant metal alloy, Super Locksfit any COMP Cams 10 degree retainer.