Retail Box, Hot Plug Drive assembly to add to or directly replace a failed 400739-B21 7.5K RPM, replacement part number 104660-001 on select Compaq ProLiant servers with card edge drive storage backplanes. This drive is NOT Universal. This 18.3GB 10,000RPM Low Profile (1.6" STD, 1" Optional) Hot Swap Drive has a 4MB Cache and a Ultra160, Ultra3 and Ultra2 interface compatible with all HP/Compaq Proliant Servers listed below. The Price for 18GBs is the same as for 36GB! 36GB can replace an 18GB in an existing RAID configuration as 18GB! Formatted Capacity: 18.3GB Compression: (Native/Uncompressed) Data Storage Device Type: SAS (Server Attached Storage) device Hard Drive Device Type: Internal hard drive Interface Type: 80-pin Ultra 160 SCSI Interface: Ultra, Ultra2, Ultra160, Ultr3, Wide SCSI Formatted Internal Transfer Rate (Min.): 26.7MB/sec Formatted Internal Transfer Rate (Max.): 40.2MB/sec External I/O Transfer Rate (Max.): 160MB/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 72MB , 147GB and 182GB Versions! 15,000 RPM Option Available! Availability: Usually ships the next business day. 400739-B21 oOriginal Retail Price: $309.00Our Current Price: $321.00Options: No Options15,000 RPM(+109)