SINGLE BULK PACK WD Caviar Black WD5003AZEX 500 GB SATA 6 Gb/s 64 MB Cache Internal 3.5-inch Desktop Hard Drive. WD Caviar Black WD5003AZEX drives combine a high performance electronics architecture with a rock solid mechanical architecture to deliver the perfect storage solution for your fully-loaded PC or maxed out gaming machine. Cool drive operation, no-touch head technology, leading-edge vibration protection ensure enhanced reliability.