Features: Double NVMe PCIe Adapter can add 2x M.2 NVMe SSD Slot via PCIe 4.0 x16, but also expaind PCIe x16 slot (x8 Signal), which can use for expanding any other PCIe Device. Compatible for M.2 PCIe NVMe SSD in all size:110x22mm, 80x22mm, 60x22mm and 42x22mm, 30x22mm; Not support any M.2 (-Base B+M Key) SSD; Motherboards Compatibility: Most Server and X299, X399 can support PCIe x8x4x4 Bifurcation. Upgraded Design: Two Slots of NVMe SSD are on positive and negative side. So the card is in small size, And individual LED Indicator design will show each SSD Working Status The PCIe x16 Slot is very useful when there is no more PCIe Slot on motherboards. Please note: 2Port NVMe PCIe Adapter do not Support Hardware Raids, only supports the formation of soft raids in Win10 , or you may build raids via Third Software, and 2 SSD should be same model. The motherboards need support "PCIe x8x4x4 Bifurcation", all of the slots will works in full speed. If MOBO only supports "x4x4x4x4", the expanded PCIe x16 will only have x4 signal. If MOBO do not support"PCIe Bifurcation" , Only the PCIe x16 works, None M.2 SSD can be recognized. Please check Motherboards user manual on its official website if you are not sure the Mobo can support. Specifications: Component:ABS Size:Approx.150x38mm/5.9x1.49inch Hardware requirement: There is available PCIe 4.0 or 3.0 x16 Slot ON M The motherboards can support PCIe x16 Bifurcation itself, and can be set as"PCIe x8x4x4" in BIOS. All of the SSD are M.2 PCIe (M Key) NVMe SSD. CPU have enough channel to support. Package Includes: 1pc M.2 NVMe to PCIE Adapter 1pc Screw Driver 2pcs M.2 screw note: Please allow 1mm errors due to manual measurement. Due to the differences between different monitors, the picture may not reflect the actual item color.