You no longer touch the wall with your fingers (no soiling).
Screw or glue tight.
To screw together: Two countersunk screws M3 x 14 (up to M3 x 30)
For fastening: Two countersunk head spax screws with 3 to 4mm shank diameter. 8 mm of the length is within the printed part. Screw spacing 38 mm. Or double-sided adhesive tape 3M VHB, 20 mm wide.
Print with PLA or PETG.
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The author marked this model as their own original creation.