Hansgrohe Unica'A 27820 Serie Instrucción De Montaje página 35

Where the contractor mounts the product, he should ensure that the entire area of the wall to which the
mounting plate is to be fitted, is flat (no projecting joints or tiles sticking out), that the structure of the wall is
suitable for the installation of the product and has no weak points.
The enclosed screws and dowels are only suitable for concrete. For another wall constructions the
manufacturer's indications of the dowel manufacturer have to be taken into account.
Adjust the dimensions to the tile pattern if required.
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