“Standard” Version II Diverter.
This diverter stem is used in many of the later Version two installations where the middle handle wasn’t controlling the drain. 5 5/8″ long, rounded edge on bonnet nut rather than square. Replace this only if your valve isn’t diverting water to the showerhead properly, and it is highly recommended that the seat (#86-9090) be changed as well. If your valve is dripping from the spout when off, check/change the hot/cold stems #86-8001 and #86-8002.
Rebuild kit for this application is #94-AS62.