genuine Apple OEM Seagate Barracuda 7200.12 500GB internal 3.5" SATA hard drive (Model: ST3500418AS / Apple P/N: 655-1564D), operating speed 7200 RPM. This drive features official Apple firmware, making it fully compatible with vintage Mac systems without triggering errors or fan speed control overrides. It comes pre-mounted in its original metal iMac mounting bracket with the alignment pins attached on the side, offering a seamless, direct drop-in replacement for a quick system restore.