This is a scanner stand for mobile phones. Cut a standard 25 mm PVC pipe to size, push it through the printed parts, lock the bottom part to the table using a bar clamp and you are done.
Optionally you can put M6 nuts and bolts to the parts but basically the friction between the parts are strong enough to hold the parts together securely.
The phone holder was designed to fit an iPhone XS Max with a case but feel free to change the size, the pipe diameter, the pipe leaning angle (or whatever else you wish) in de parametric Fusion 360 design: https://a360.co/2SNNiqb