Satechi has launched the USB-C Slim Dock for 24-in iMacs. The dock features a built-in NVMe SATA NGFF enclosure compatible with M.2 SSD. Also included are multiple ports, such as USB-C and USB-A ports, capable of data transfer speeds up to 10 Gbps; however, these cannot be used for charging.
https://www.notebookcheck.net/Satechi-USB-C-Slim-Dock-for-24-in-iMac-launches-with-built-in-SSD-enclosure.625563.0.html