The AS6004U utilizes a USB 3.0 connection cable. Simply plug it into any ASUSTOR NAS to complete hardware expansion! Depending on the model, ASUSTOR NAS devices can simultaneously connect up to 3 AS6004U units, satisfying the high capacity storage demands of enterprise users. The security bracket and mounting hole design allow the AS6004U and USB cable to be connected securely without having to worry about disconnections. In order to help users avoid accidentally pushing disk tray buttons and releasing hard disks during operation, ASUSTOR has added a new lock mechanism to its hard disk trays. The lock’s flat-head design ensures that users will not need any special keys or tools to unlock it, only a simple flat-head screw driver. The disks trays can be used with all ASUSTOR NAS devices, providing an additional layer of security for applications requiring the frequent swapping of hard disks (e.g., MyArchive).