The MobileSTOR MS4UT+B is a 4-bay hardware RAID 5 storage tower that utilizes high performance USB 3.0 and eSATA interfaces to provide over 200MB/s in performance. The included USB 3.0 port is backwards compatible with widely available USB 2.0 ports, which is a convenient feature when both USB 3.0 and eSATA connections are unavailable. With built-in RAID 0, 1, 10, 3, 5 and spanning, the MS4UT+B provides hardware RAID redundancy protection against hard drive failures. The RAID engine is embedded within the enclosure and performs all RAID parity calculation to reduce CPU utilization from the host PC. RAID controller cards are unnecessary. Four hot-swappable hard drives slots are behind the front cover to allow easy trouble shooting and hard drive replacement. The newly trayless design allow easy installation. With adjustable cooling fan design, and high performance transfer rate to support various audio and video editing problems, MS4UT+B is the ideal storage tower for high-end computing.