Mark & Juanita wrote:
496: Split shaft coupler. woodruff key goes into square portion of shaft
and coupler, bolt tightens coupler onto shaft.


Sorry, but it's not a coupler. Couplers are longer, and have setscrews
for each shaft. This is a shaft collar. The slot has nothing to do
with a Woodruff key, but is there to allow the collar to collapse
easier.

John Martin