This Mini SAS (SFF-8643) to 4x SATA Cable, SFF-8643 is host , connect to the motherboard or RAID Controller with Mini SAS ports. 4x7Pin SATA is the target , connect to the hard drives with SATA port Before you buy this cable , please make sure the Mini SAS (SFF-8643) on your motherboard or RAID Controller. If the Mini SAS (SFF-8643) on your backplane, this cable will not work with them SFF-8643: the new connector uses less PCB real estate and allows higher port density for internal hosts and devices. Hybrid versions of these new cables will allow for a smooth transition from 6Gb to 12Gb. Serial Attached SCSI (SAS) is a high-speed data storage interface designed for high-throughput and fast data access Cable Length 1.6ft/0.5M