The MCS-7845I-2.4-ECS1 is a MCS 7845I-2400 targeted at Unity deployments supporting voice messaging only. It is equipped with dual Prestonia Xeon 2.4GHz processors, 1 GB SDRAM, four 36 GB SCSI hard disk drives (RAID1 configured) plus two 72 GB hard disk drives (RAID 1 configured) and redundant power supplies. A single MCS-7845I-2.4-ECS1 can support up to 2200 voice messaging subscribers.