The IBM TotalStorage DS4000 EXP100 Storage Expansion Unit supports a maximum of fourteen DS4000 250GB SATA disk drive modules with 3.5 TB of capacity per enclosure. The DS4000 EXP100 offers SATA technology and delivers redundant 2Gbps Fibre Channel connections. The DS4000 EXP100 is designed for the DS4300, DS4400 and the DS4500 and is a rack mountable enclosure. Frontier offers IBM TotalStorage Expansion Units used or refurbished. Call Frontier today or request a quote. 866-226-6344