JB 3060 This high density 4U 60-bay JBOD expansion enclosure provides additional storage capacity and higher performance to your existing EonStor DS 4000 storage solution through 12Gb/s drive side SAS interface connections. When combined with the JB 3060, EonStor DS 4000 can support up to 444 drives, making a great choice for flexible scalability. Available in single or dual controller configurations, it features hot-swappable modular redundant 80 PLUS power supplies for ease of maintenance and high availability.