Add four 35 sata iii hard drives to your computer externally through usb 30 with uasp or esata the s3540bu33e 4 bay hdd enclosure lets you install four 35 sata hard drives into an external enclosure and connect to your computer through usb 30 or esata for fast performance and efficient data transfers the enclosure supports sata iii transfer speeds up to 6 gbps when connected through esata the versatile enclosure can also be connected through usb 30 with support for uasp perfor