Introducing the MB994IPO-3SB, a full metal dual bay 2.5 SATA/SAS hard drive / SSD mobile rack backplane designed with a Slim Optical Disk Drive (ODD) slot for use in a single 5.25 device bay. It's a perfect device designed for small form factor system or server such as: IPC, HTPC, NAS, Home Servers and All-In-One computers. Dual 4-pin power connectors are used to ensure secured and consistent power supply to both drives and ODD, whether they are low power consumption 2.5 SATA SSD's or power hungry 15000 RPM 2.5 SAS drives. Also included is a single 40mm cooling fan with on & off switch to assist the drives running at their optimal temperatures, in even the most intense applications.