This fits the fingernail profiler jig.

The Long Grind Jig (PELGJ) can be used in conjunction with the Robert Sorby Fingernail Profiler, the Deluxe Universal Sharpening System or the ultimate sharpening system the Robert Sorby ProEdge. It allows for three different types of profile to be produced on bowl and spindle gouges. It will produce a fingernail profile, a long grind and an extra long grind depending on which location hole the profile arm is placed.

It fits onto the bar in replacement of the original fingernail jig that is standard on the ProEdge and is used in exactly the same way but with advantage of three choices.