Vintage Bench Drill Press Refit Square Tenon Machine Mortise Machines Converter

Please see photos for accurate representation of box and contents. Box had some duct tape on it at one point I think because there is some faint staining from residue. I think one of the bits is missing - I see an empty slot next to the two other bits. I assume all other parts are present, there aren't any instructions. I inherited this and have no idea how to use it and only barely know what it's used for - Thank you google image search - lol. The storage box for this is about 8 inches x 8 inches x 5 inches. it's heavy - weighs about 7 lbs. I think if you are making tennons in woodworking, this helps convert square holes? There are a couple of what I think are bushings in the set as well as two bits - I'm fairly certain the third is missing.