Simple modified Belt/Key Holder.
I made the main part longer; Indented the back of the main part to hold tape, glue or silicone; Made two end caps (left and right) to stop the belt hooks from escaping; Made some double hooks, because the single hooks are slightly annoying to use and are less stable.
The ‘RoundBuckle’ part has a smaller middle section than the 'SquareBuckle' part, for added stability.
Print all parts with brims for stability, and to stop warping on the main part.
Supports only needed on the ‘RoundBuckle’ and ‘SquareBuckle’ parts, if your printing them sideways (for extra strength).
Big thanks to Rattiso for the original - https://www.thingiverse.com/thing:3045777.
The author remixed this model.