Add 4 Removable SATA/SAS Hard Drives through a Single 5.25in Bay. The SATSAS425BK 4-Drive 2.5in SATA/SAS Hot-swap Backplane lets you install four 2.5" SATA and/or SAS hard drives into a single 5.25in front bay. Using removable trays, each drive can be replaced or swapped out without having to open up the computer chassis. Each removable tray features a locking mechanism that prevents unauthorized removal of the drives, and also power and activity LEDs. Constructed from lightweight and durable aluminum to help with heat dissipation, the backplane also features a 40mm cooling fan to help increase air flow.