Cleveland Twist Drill Company Concave Milling Cutter, 3-1/2" diameter x 5/8" diameter circle x 1-1/4" bore. Very sharp. The machine shop that I bought the lot of tools from kept everything nice and sharp. It has been sharped a number of times, but still has plenty of life remaining. I bought all the gear cutters, slotting, concave, convex, and many end mills from a large machine shop that closed. I probably have nearly every size gear cutter made in 14.5 PA except for very large ones in triplicate or quadruplicate, some new, most lightly used and well maintained. If you are looking for something specific, let me know.
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