I made this simple collection of interlocking parts to make a customizable length rack for organizing baseball caps, but could be used for other light weight items that fit on the hooks such as ties, belts, etc.

For standard baseball caps you will need the following.

One Type A, this has a screw hole for mounting it to a surface.
For each hat you need One Type B (the one with a garment hook) and One Type C (the blank extender).

Assembly

Insert the peg into the hole at a 90 degree angle first, then slide the peg down and rotate the pieces to be in line with each other.

For best results position the Type C part so that the peg facing the opposite direction. (peg should not be visible on the blank version when looking at the type A or Type B plates.)

Print instructions

Resolution: 0.20mm speed or quality
Material: PLA/PET-G
Filament Profile: Prusament PLA
Filament Brand: Spool 3D Black
Detect Thin Walls: Disabled
Extra Perimeters: Disabled
Printer: Prusa MK3S, Ender 5+
Supports: Not required, but will improve end result print quality of the peg and hooks.