This lot includes four Western Digital 500GB internal desktop drives, model WD5000BLHX from the Constellation product line. These drives have a rotation speed of 10000 RPM and are compatible with both PC and Mac. They have a SATA interface and support HDD drive types. The 2.5 inch form factor and 15mm size make them a great fit for many different computer setups. In addition to their high storage capacity and compatibility, these drives also come with hot swap and removable features for added convenience. They have a sleek silver color and are in excellent working condition. Whether you are upgrading an existing computer or building a new one, these Western Digital drives are a reliable choice for all your storage needs.