This is a modular hat rack.  Print as many middle pieces as you want and just one top and bottom piece.  Join each piece with a piece of filament.  Mount to the wall with Command Strips.  You shouldn't need a mount for each piece, but might need at least 3 (top, bottom, middle) depending on the number of pieces you use and the weight of the hats you put on it.  (It should be obvious, but you will need to orient each piece to be flat on it's back to print, sorry for not adjusting this first).