Western Digital WD Purple 8TB 3.5" Surveillance HDD 256MB Cache SATA 3-Year Limited Warranty Specifications Features - Engineered for mainstream surveillance systems. - WD AllFrame technology delivers optimizations for write-intensive, low bit-rate, high stream-count workloads typical to mainstream surveillance applications. - Supports up to 180TB/yr workload rate and up to 16 bays. Capacity_ 8 TB Interface_ SATA Form Factor_ 3.5 Inch Recording Technology_ CMR Compatibility Up to 64 HD cameras / Up to 16 drive bays / AllFrame firmware technology Transfer Rate up to 215MB/s Disk Speed (RPM) 5640 RPM Cache Size 256MB Warranty 3-Year Limited Warranty Dimensions (L x W x H) 5.79" x 4" x 1.03" Weight 720gms Model Number WD85PURZ Operating Temperature 0°C to 65°C Non-Operating Temperature -40°C to 70°C Certifications BSMI, ICES-003/NMB-003, CE, FCC, KC, Maghreb, RCM, UKCA, VCCI, CB-Scheme, TUV, UL