Sorby TRAC Tool Rest Adjustment Collar, 5/8 in. The Sorby TRAC Tool Rest Adjustment Collar is designed to solve a common issue faced by woodturners when adjusting their tool rest height. Often, when the locking handle is released, the tool rest drops, causing the preferred height setting to be lost. This innovative collar ensures that the tool rest remains at the set height even when the locking handle is released, allowing you to move the tool rest to a new position without the need to reset the height before locking it in place. With the TRAC, you can easily adjust the tool rest height up or down by up to 1/2 inch (13mm) simply by turning the outer adjustment ring. The Acetal seating disc provides smooth and effortless operation. For optimal adjustment, it is to set the outer ring so that about 1/4 inch (6mm) of the inner ring is protruding, enabling easy vertical movement. Model Number: LRSTRAC16