Very rare type of thunderbolt dock that has a built in 4TB HDD and an expansion bay for an NVMe SSD- both Mac and pc compatible. Works PERFECTLY. I am the sole buyer and user. Complete with box as if it came new-Includes all original power cables and thunderbolt 3 cable. Lightly used great physical condition. No returns. The Seagate FireCuda Gaming Hub 4TB with NVMe Expansion Bay is a high-performance external hard drive designed for gamers and content creators. With a storage capacity of 4TB, it offers ample space for storing large files and games. The unit features RGB lighting for a customizable and visually appealing look. It is compatible with both PC and Mac systems and offers fast read and write speeds, thanks to its HDD and SSD storage format. Additionally, it comes with a 1-year manufacturer warranty and is equipped with USB 3.0 for easy connectivity. Overall, this product is a valuable addition to anyone looking to expand their storage capabilities.