Introducing the FlexCage MB974SP-2B, a 4-in-3 Tray-less SATA Backplane Cage, designed to maximize space use by allowing up to 4 x 3.5" SATA III hard drives, while only consuming three 5.25" device bays. The FlexCage brings enthusiast preferred features such as: plug & play Tray-less design, replaceable 80mm cooling fan, 3 speed fan control with Smart Cooling Technology, integrated USB 3.0 hub, and full control of your drive with individual childproof power buttons. The included 80mm cooling fan also can be also easily replaced and maintained, compatible with most aftermarket 2 or 3 pin cooling fans of the same size. To ensure a peace of mind, the FlexCage is backed with our 3 year warranty, equivalent to a hard drive"s warranty. It is designed to be used in consumer and enthusiast systems such as, gaming / media computer cases, and home servers that hot swap frequently.