FYH has reinvented the adapter sleeve.

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 adapter 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 adapter 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.

Tighten the set screws by hand. Tightening the set screws creates extreme holding power over traditional adapter sleeves without any change to the bearing clearance.

A traditional UK unit requires many tools to be assembled. You must tighten the lock nut using a torque wrench and following a torque tightening chart. Over tightening of the adapter creates smaller clearance which can affect bearing life.