The 3U 16-bay storage expansion enclosure TL-R1620Sdc SAS 12Gb/s features dual controllers, an OLED indicator, and a low-profile rack design, making it ideal for expanding NAS storage capacity with a dual-controller QNAP. Both controllers have three Mini-SAS HD (SFF-8644) ports supporting 12Gbps SAS and Broadcom SAS DataBolt bandwidth optimization technology. The dual-direction mini-SAS design ensures continuous operation even if an external JBOD cable is disconnected. Up to 7 TL-R1620Sdc units can be connected via high-speed Mini-SAS HD cables, providing scalability and high reliability for critical storage applications such as file servers, virtualization, monitoring, mid-sized data centers, multimedia, and more.