How to use an NVMe drive to upgrade your Mac's SSD | AppleInsider
How to install an SSD on a 15-inch Retina MacBook Pro
MacBook Pro (Retina, 13-inch, Early 2015) Upgrade to NVMe M.2 SSD - YouTube
OWC 1.0TB Aura Pro X2 SSD Blade Only For MacBook Air Mid 2013 - 2017, MacBook Pro Retina, Late 2013 - Mid 2015, and Mac Pro Late 2013 Computers. Model OWCS3DAPT4MB10 Internal SSDs - Newegg.com
661-02531 Apple SSD Flash Storage 1TB for MacBook Pro Retina 15" Mid 2015