This is the ball bearing version of our patented revolutionary locking system, Z LOCK. The new series is called ZK
and utilizes a tapered bore UK insert with our original Z LOCK sleeve instead of a traditional adaptor sleeve. The
units are pre-assembled at the factory and are ready to use straight out of the box unlike traditional units that have
separate inserts and adaptor sleeves. The installation of ZK units is extraordinary. ZK uses one key to tighten just
two set screws by hand. ZK requires no torque charts and does not affect the inner clearance of the bearing at all