You put the metal base on the wall and then simply attach the shelf to the base... the shelf is not secured in any way to the base, it just rests on top of it, without even being wedged, resulting in it not being straight and moving... it can easily come off its position.
Could I have done it wrong... but it's impossible to make a mistake, there is only one base and one shelf in the package, nothing else, no plugs or screws.
However, it is beautiful