Very Nice, Looks like it has only been used one time. Shank size 34.51mm from Flat to Tip of the triangle shaped shank.
The diameter of the cutting head is about 39.4mm so with an insert in it your minimum bore hole size would need to be a little larger than that. I could not find details about this tool on the Sandvik site.
Spot facing reverse LH Left Hand Cut back side counterbore indexable boring toolholder. The item "SANDVIK Carbide Boring bar Reverse Facer Mill Cutter Back Facing Tool Holder" is in sale since Friday, January 11, 2019. This item is in the category "Business & Industrial\CNC, Metalworking & Manufacturing\Workholding & Toolholding\Toolholding\Other Toolholding". The seller is "dj-machinery" and is located in Grand Rapids, Michigan.
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