M.2 NVMe to PCIe 4.0 X4 Adapter: Converting one PCIe X4/X8/X16 slot on the motherboard to the M.2 Key M slot allows you to install M.2 NVMe SSD into this Key M slot. Without a mounting bracket, it is suitable for compact cases or 2U high cases. Suitable for horizontally placed motherboards. If the motherboard is placed vertically, the adapter may tilt (due to the weight of the adapter + SSD) FCC and CE certified, Highly Reliable, and Stable PCIe X4 Full Speed: The M.2 NVMe SSD speed is unaffected, just as if it was installed on the motherboard No limit to the capacity of the M.2 NVMe SSD: Support 2T/4T Support OS Booting: Reinstall the OS, and set up BIOS/UEFI boot from this M.2 NVMe SSD (Note: Some motherboards are too old to support OS booting. In this case, M.2 NVMe SSDs can be used as storage disks) Plug-and-play in Windows 11/10/8/Linux/Mac OS (Note: Not support Windows 7). The new M.2 NVMe SSD needs to be initialized and formatted before it can be recognized by the computer host.