The more time goes on, the lower prices go. Depending on where you live, you should see whether eBay or similar have Apple OEM drives at a low enough price for you.As an example of something I don't get into, there are some Mac Pros which have some NVME adapter cards for their PCIE bus - (though I think the link I provide below to a big Mac Pro thread does include that info, if that's what you're after).Ī really great resource for understanding Apple removable SSDs is the following which goes from the first MacBook Air drives to Polaris: I am specifically considering adapters for Apple-proprietary SSD connectors capable of running an industry-standard protocol (SATA or NVME). If there are other threads to which I should reference, let me know, I'd love to include them. There are very good Macrumors threads for significant parts of it, to which I link. I figure why not summarize this info, since I haven't seen such a summary elsewhere. I started looking at this when considering a non-Apple SSD upgrade for my rMPB 11,1 and 11,4 - and went down the rabbit hole. (links to Amazon, etc, are for information purposes only - none of them is an affiliate link) CORRECTIONS WELCOMED, ALL ERRORS ARE MINE, USE AT YOUR OWN RISK.