. WD TB AV-25 2.5 5400RPM 16MB SATA 3Gb/s Internal Hard Drive . 24 x 7 reliabilityThese drives are designed to last in always-on streaming digital audio/video environments such as DVR/PVR digital video surveillance and other demanding multimedia applications.Advanced format technologyLeading edge technology delivers improved video quality and AV performance through enhanced error correction capability.SilkStream technologyOptimized for smooth continuous digital video playback of up to five simultaneous HD streams. SilkStream is compatible with the ATA streaming command set so AV customers can use standard streaming management and error recovery options.Ultra-cool operationA cool drives is a more reliable drive. WD continues to develop new and innovative ways to keep drives cool while they are operating.QuietNoise levels have been minimized to less than one sone - virtually below the threshold of human hearing.Low power consumptionThe drive draws less than 2 Watts while operating and a mere 4.75 Watts during spin up.1 million hours MTTF (MTBF)Best-in-class reliability for small-form factor AV storage.Preemptive Wear Leveling (PWL)The drive arm frequently sweeps across the disk to reduce uneven wear on the drive surface common to audio video streaming applicationsWD AV-25 2.5-inch SATA hard drives are specially engineered to offer cool quiet operation while providing maximum reliability in 24 x 7 always-on environments. With support for up to five simultaneous HD video streams these drives are perfect for DVRs digital video surveillance and other demanding multimedia applications..