#5101 30-Disk Expansion Feature: A disk unit enclosure feature for the #5065 & 5074 Storage/PCI Expansion Tower. #5101 includes two 15 disk unit enclosures, a 700-watt power supply, backplanes and cables. One PCI Disk Unit Controller is required to support the 15 disk units in each of the two disk unit enclosures included with #5101 & #5074. OS/400 V4R4 with PTF MF22587, or cum PTF package C9229440, or later, is required. Maximum: One per #5065 or #5074