SNT-SAC3141B 4x 3.5&rdquo; HD in 3 x 5.25&rdquo; Drive Bay Hot Swap SAS/SATA Backplane Rack Maximum Capacity: 8TB ( 4 x 2TB Hard drive) Interface: SAS/SATA I  II Support Plug & Play and Hot Swap LED for power, HDD access, fan sensor and reset Safety lock on each tray