A USB-C to Type-C interface with a transfer speed of 40Gbps is possible. This would require the use of the USB 3.2 Gen 2x2 specification, which supports a maximum transfer speed of 20Gbps per lane. By utilizing two lanes, it would be possible to achieve a total transfer speed of 40Gbps. It's important to note that not all devices and cables support this high transfer speed. Both the device and the data cable need to be compatible with the USB 3.2 Gen 2x2 specification to achieve the 40Gbps transfer rate. Additionally, the actual transfer speed may also be affected by other factors such as the performance of the connected devices and the quality of the cables used. If you are looking for a USB C to Type C Data Cable with a 40Gbps transfer speed, make sure to check the specifications and compatibility of the cable and devices you plan to use.