ICY DOCK MB154SP-B 4 in 3 I, II & III module SATA 6Gbps Hot-Swap HDD Backplane Module Cage Rack. Introducing the MB154SP-B, a 4-in-3 SATA internal RAID hot-swap backplane for 3.5" SATA hard drives. The MB154SP-B has been redesigned to be a lighter module, while maintaining the same level of quality, build and service you?d expect from an Icy Dock product. The space saving design is still established with the backplane module allowing up to 4 x 3.5" SATA III hard drives, while only consuming three 5.25" bays. 15 pin SATA power is used to provide better accessibility for various host systems. The cooling has been improved to provide better air flow to your hard drives, by using a full metal body for the best heat dissipation possible. In addition, our enhanced direct air flow design allows the included cooling fan to raise its efficiency to cool down your hard drives, by sealing and rerouting any vents around the fan to route incoming air directly to the cooling fan. In addition, the backplane logic PCB has larger vents in key areas to allow more air to flow into and exit the MB154SP-B, making it an ideal system to store and cool your hard drives. The MB154SP-B has also kept the same interchangeable EZ-Tray used in MB45X, MB559 and MB561 series, allowing you to continue to use the same trays from these series without any issues regarding switching to new designs. The EZ-Tray accepts most 3.5" SATA hard drives and is very easy to install / remove to the device in two steps press the release button and pull / push the lever. The included 80mm cooling fan also can be easily replaced and maintained, as the unit it can be fully removed and replaced with aftermarket cooling fans of the same size. To expand the range of compatible fans, both 2 and 3 pin fan power ports are available and can be easily accessed.