However there is now on the market an adapter to allow you to fit standard M2 SSDs in to Apple's proprietary socket. OWC do make an SSD with the same proprietary Apple connector meaning it will fit with no extra effort. This in turn means that if you ask Apple they will probably tell you you need to get a replacement part from Apple. This means a standard M2 SSD will not fit.
The Mac Pro 2013 like other Mac models of that era uses a PCIe SSD with a proprietary (Apple) version of the standard M2 connector.
