Question about i-tec USB C to

The specification "up to 2x 4K @ 30Hz" means that the adapter can support two monitors with a resolution of 3840 x 2160 pixels (4K) each and a refresh rate of 30 Hz simultaneously.

The following applies to your two screens with a resolution of 1920 x 1080 pixels (Full HD) and a refresh rate of 60 Hz: The adapter can support these resolutions and refresh rates without any problems, as Full HD at 60 Hz is below the specifications supported by the adapter. You can therefore use both monitors with these settings without having to reduce the refresh rate to 30 Hz.