Review on 🔌 StarTech.com U.2 to M.2 Adapter – PCIe NVMe SSD Adapter for 1 U.2 Drive – M.2 PCIe x4 Interface – U.2 to M.2 PCIe Adapter – Enhanced U.2 SSD Converter (M2E4SFF8643) by Kimoni Arenas

Runs macOS Catalina v10.15.6 on a Micron 9300 MAX 6.4 TB U.2 SSD; On my iMac (Retina 5K, 27-inch, 2017) Intel Core i5 quad-core @ 3.4 GHz via: Highpoint RocketStor 6661A Thunderbolt 3 - PCIe 3.0 X16 expansion chassis; StarTech.com U.2 to PCIe to x4 PCIe Adapter for 2.5" U.2 NVMe SSD - SFF-8639 PCIe Adapter - U.2 SSD - PCIe SSD to U.2 Drive (PEX4SFF8639). Had to have System Integrity Protection over disable terminal (disable csrutil) install Catalina from boot into Command-R (download from web) On this iMac the drive runs on a TB3 connection at about 2400 read/writes per BlackMagic Disk speed test Runs hot with constant use , but the speed of Micron 9300 MAX 6.4TB U.2 SSD remains stable.