I noticed that we only had one insert for our boring bar at work and went on MSC to order more. When I found the page with the different categories on inserts, I noticed that there were Boring Inserts and Milling Inserts. I know that they both come in all shape and sizes, but both do come in the triangular shape that I was needing. Now I ordered the right one, but I got to wondering, what is the difference in those two type of inserts? And are they interchangeable?