I have a FS 9MM Pro series M&P. I just noticed that on the underside of the slide, there are 3 dimples. Maybe they have always been there and I have never noticed.
Just want to make sure this is normal. Gun has 0 malfunctions with about 2000 rounds downrange.
Normal, the consensus from past discussions about this is that it's to identify which milling machine made that particular slide so that if there's ever a warranty problem somewhere down the line that has to do with machining they know which machine to check for problems.