The fischer cavity metal anchor HM-S is a versatile cavity fixing with a metric screw for all panel building materials. The fixing is set with the fischer installation pliers HM-Z 1 in the pre-positioned installation. The fixing is pulled in the cavity against the board building material with the pliers. In this case, the expanding arms swing open and press onto the reverse side of the board. Alternatively, assembly can be carried out either with a screwdriver or a cordless screwdriver. The cavity metal anchor HM-S is suitable for fixing lights, towel rails, and curtain rails.