I designed this clipboard to hold the RocketBook Flip. I felt it justified something more sophisticated than a generic clipboard. It also doesn't interfere with the RocketBook App scan.
The two parts are held in place with thin double side tape and attached to a 230x290x6mm acrylic sheet. The pad slides nicely in from the right side and is held relatively securely by the three little ridges. If you feel it is too tight they can be filed down a bit.
Also see…
https://www.printables.com/model/460960-rocketbook-mini-sleeve
The author marked this model as their own original creation.