Retail Box, Hot Plug Drive assembly to add to or directly replace a failed 128420-B21, replacement part number 143916-001 for select Compaq ProLiant servers with card edge drive storage backplanes. This drive is NOT Universal. This 73.4GB 10,000RPM Low Profile (STD 1.6" Opt 1") Hot Swap Drive has a 4MB Cache and a Ultra320,Ultra160, Ultra3 and Ultra2 interface compatible with all HP/Compaq Proliant Servers listed below. Formatted Capacity: 73.4GB Compression: (Native/Uncompressed) Data Storage Device Type: SAS (Server Attached Storage) device Hard Drive Device Type: Internal hard drive Interface Type: 80-pin Ultra 320 SCSI Interface: Ultra, Ultra2, Ultra160, Ultra3, Ultra320, Wide SCSI Formatted Internal Transfer Rate (Min.): 26.7MB/sec Formatted Internal Transfer Rate (Max.): 40.2MB/sec External I/O Transfer Rate (Max.): 320MB/sec Average Seek Time Read: 5.2ms typical Default Buffer: 4MB Spindle Speed: 10033 RPM MTBF: 1,200,000 hours S.M.A.R.T. Support: Yes Warranty: 3-year Compatibility: Proliant Models: Storage System/U, 7000, 6500, 6000, 5500, 300, 1850r(450 & Below) and 850r. Other Proliants with card edge backplane but speeds may vary due to lack of Ultra2/3 controllers. Also available in 147GB and 300GB Versions! 15,000 RPM Option Available! Availability: Usually ships the next business day. 128420-B21 oX$397.30