how do I buy the flash storage for upgrade for a mac pro late 2013

http://eshop.macsales.com/search/2013+mac+pro+sorage

but note these are slower than the Mac storage

http://barefeats.com/hard197.html

PCIe-SSD for New Mac Pro 2013

Note that the blade SSDs for later model MacBooks will fiut in the Mac Pro but they are slower. The ones in the MacBook do not have the blac blade covering (which is a heatsink)

how do I buy the flash storage for upgrade for late 2013 mac pro

You don't. Apple will repair it if it breaks, but does not offer an upgrade, because it is not needed.

That SSD is intended as the Boot Drive, and you move your User files to another drive such as one or two USB-3 drives or a ThunderBolt enclosure.

User Tip: Creating a lean, fast Boot Drive

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