UGREEN USB 3.0 4-Port Switch Underware holder compatible with Multiboard system.
It was made by Underware 2.0 Customizer.
Link: https://handsonkatie.com/underware-2-0-the-made-to-measure-collection/
Link to multiboard: https://www.multiboard.io/
To connect holder to multiboard use Flush Multiconnect - generic multiboard connector.
Link: https://makerworld.com/en/models/1026736#profileId-1017464
The author marked this model as their own original creation.