Supports 4x 2.5" SAS/SATA HDDs/SSDs (up to 9.5 mm drive height); Install into any standard external 5.25" drive bay; Supports SATA 6Gbp/s transfer speeds & SAS up to 12Gbp/s (SAS host required); Tray-less and door-less design for hot-swapping bare drives without tools or screws; Reduce cable clutter by using a single 15-pin SATA power connection to power four drives