Vintage Ferrees G71B Bell Tenon Set for Bb Soprano Clarinet. Sealed Package
Taken from Ferrees: "The taper of the arbor fits clarinet bores better and acts as a pilot;
making a more accurate cut with less chance of the cutter drifting off
center. The cutter is held in the lathe chuck and reversed to make the
step cut, if necessary. You can do a better finished job than by trying
to thread a new tenon in, or some other method."