Patented connection and adapter design uses spring-loaded stainless steel ball bearings to securely attach connected cups and adapters to the C-frame and forcing screw Works with most OTC ball joint kits, cups and adapters Locking cups and adapters set up faster on the vehicle and leave one hand free Starter kit option (CA7149) includes 7 cups and adapters to work on more than 230 vehicles models, 38% more than the competition No O-Rings or removable fasteners to lose, damage or replace. For R&I of ball joints, U-joints, wheel studs and more