This is Delta no. 43-990.  This is an arbor used on the radial arm saws to mount 1/2" bore shaper cutters.  It was used with the 33-304 or 33-277 adaptor.   There are no returns on any of the items in the NOS catagory.  Please look carefully to be sure it will fit your machine.  Email me if you have questions. Shipping on this item is free via USPS or UPS. I do combine shipping wherever possible. I do ship internationally. Just email me and I will quote shipping to your country.