Top quality tool from MRB, this is to pull the layshaft into the rear hub bearing (also known as the final drive pulling sleeve)
 
It is important when fitting the layshaft and checking the tolerances in the gearbox, that the layshaft is pulled all the way into the rear hub bearing as far as it will go.
 
One way is to use a hammer then fit the rear hub and tighten it up, but this can be difficult on the workbench.
 
As an alternativee, Mark Broadhurst came up with this sleeve design.
 
offetr the layshaft into the bearing, fit the sleeve locating the allen screw in the layshaft grooves, fit the special nut provided, hold the slrrve with a spanner and tighten the nut until the layshaft is drawn into position, when it locks up remove the allen bolt and refit into the next hole.
 
Ideal to fit the layshaft and keep it tight so the gearbox can be shimmed up correctly.