Yakima Baseline Tower 4PK Revolutionary tower architecture uses a new tri-axial DropHook clip adjustment motion to accommodate a wide range of roof shapes DropHook design ensures that the rack is safe and secure every time, no guesswork Risk-free torque set installation. Tool included The towers adaptable design conforms to work with Yakima RoundBar, CoreBar and JetStream bars Up to 12 degree of pitch adjustment of bar angle so that front and rear crossbars are as level as possible