Western Digital Purple 3TB 3.5” SATA Surveillance Internal HDD Key Features 3TB Internal Surveillance HDD 5400 rpm Rotation Speed Designed for 24/7 Security Cameras SATA 3 Interface 3-Year Limited Warranty Overview WD Purple Surveillance Storage offers exclusive AllFrame technology to bring you premium reliability and peace-of-mind when installing your home or small to medium business security system. WD Purple’s exclusive firmware upgrades work with ATA streaming to reduce error pixilation and video interruptions that occur when desktop hard drives are incorrectly used as storage in security systems. This drive is built for 24/7, always-on, high-definition surveillance security systems that use up to eight hard drives and up to 32 cameras. Specifications Disk Type HDD Surveillance External? No Capacity 3TB Rotation Speed 5400 rpm Cache 64MB Transfer Rate up to 150MB/s Interface SATA 3 Compatibility Surveillance Dimensions 147 x 102 x 26 mm