Our 395473-B21o Hard Drive (500GB 7200RPM SATA-150/300) hot-plug hard drive with universal carrier, are highly tested, Retail Box, Hot Plug Drive assemblies, to add/join to or directly replace a failed HP 395473-B21 Hot Plug Drive. For all HP Proliant Servers with a SATA Hot Plug backplane, including: ProLiant DL140 G3, DL320 G4, DL320 G5, DL360 G4p, ML150 G2, ML150 G3, ML310 G3, ML310 G4, ML350 G4p and ML350 G5 Availability: Usually ships the next business day. 395473-B21o$499.99