1.Compliant with PCI-Express Specification v2.0 and backward compatible with PCI-Express 1.x2.Compliant with Serial ATA Specification 3.03.PCI Express x2 interface, and compatible with PCI Express x4, x8 and x16 slots4.Supports communication speeds of 6.0Gbps, 3.0Gbps, and 1.5Gbps5.Hot plug and Hot Swap6.Support Native Command Queue (NCQ)7.Supports Port Multiplier FIS based switching or command based switching8.Compatible with SATA III/II/I Hard Drives9.Support RAID function: RAID 0, RAID 1, RAID 10 and HyperDuo Model: UGT-ST644R Ports: 4 x Internal SATA 6Gb/s Ports (Backward Compatible with SATA II/I)2 x External SATA (eSATA) Ports Interface: PCIe v2.0 System Requirements: Windows XP/Vista/7/8 and Server 2008 R2. PCI Express x4, x8 or x16 slot Package Contents: 1 x 4 Channel 6-Port SATA 6Gb/s PCIe RAID Host Card 1 x Driver CD 1 x User Manual 1 x Low Profile Bracket 2 x SATA Cables Item Dimension (L''xW''xH''): 8.00 x 5.75 x 1.50Weight: 0.5 lbWarranty Information: 1-Year