JetDrive 720 | SSD Upgrade Kits for Mac - Transcend Information, Inc.
Amazon.com: Sintech M.2 NVMe SSD Adapter Card for Upgrade 2016 2017 13" MacBook PRO A1708 Non-Touch Bar Models(Only For Late 2016-Mid 2017 Year) : Electronics
Mac Studio teardown concludes once and for all: SSD storage isn't upgradeable | Macworld