Introducing the FlexCage MB973SP-1B, a hot-swappable 3 bay tray-less backplane cage for 3.5 SAS / SATA hard drives. This is a commercially designed product in the FlexCage series for use in workstation or server environments, such as ATX towers or rackmounts. This FlexCage incorporates the best technologies to meet those demands, with second to none fit, function, and reliability.