Hansgrohe AXOR Uno 41519 Série Mode D'emploi page 18

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.
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