Lenovo - Hybrid hard drive - 500 GB ( 8 GB Flash Product Details
The ThinkPad 500GB/8GB 6Gb/s 2.5" SATA Hybrid Drive option provides a robust thin design enabling a seamless upgrade from the primary hard drive of supported ThinkPad laptops. This affordable option provides solid state speed for fast and responsive system performance with 8GB NAND Flash memory. For additional storage and backup, install this drive as a second hard drive using the ThinkPad 9.5mm SATA Hard Drive Bay Adapter IV (0B47315).
Additional Resources: Product Manuals