1. Dual NVMe PCIe Adapter can add 2x M.2 NVMe SSD slots via PCIe 4.0 x16, but also expand extra PCIe x16 slot (x8 Signal), which can be used to expand any other PCIe devices. 2. Compatible with M.2 PCI-e NVMe SSDs of all sizes: 110x22mm, 80x22mm, 60x22mm and 42x22mm, 30x22mm; Does not support any M.2 (SATA based B+M Key) SSD; Motherboard Compatibility: Most servers and X299, X399 can support PCIe x8x4x4 Bifurcation. 3. Please Note: 1. The 2-Port NVMe PCIe Adapter does not support hardware RAID, only supports software RAID formation in Win10, or you can build RAID via third-party software, and the 2 SSDs should be the same model. 4. The motherboard must support "PCIe x8x4x4 Bifurcation", all slots will work in RAID. If it only supports "x4x4x4x4", the expanded PCIe x16 will only have x4 signal. If it does not support "PCIe Bifurcation", only PCIe x16 will work, no M.2 SSD can be recognized. 5. Please check your motherboard user manual on its official website if you are unsure whether it can support. Upgraded Design: 1. Two slots for NVMe SSD are on positive and negative sides. So the card is in small size, and individual LED indicator design shows each SSD's working status. 2. The more PCIe x16 slot is very useful when there are no more PCIe slots on the motherboard. Hardware Requirements: 1. There is an available PCI-e 4.0 or 3.0 x16 slot on M/B. 2. The motherboard can support PCIe x16 Bifurcation itself and can be set to "PCI-e x8x4x4" in BIOS. 3. All SSDs are M.2 PCI-e (M Key) NVMe SSDs. 4. The CPU has enough channels to support. Color: Black Material: ABS Package Contents: 1 x NVMe SSD Adapter Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture to be a little different from the real thing. The measurement allowed error is +/- 1-3cm.