Functioning The metal cavity fixing HM is suitable for prepositioned installation The fixing should be selected based on the thickness of the board building material, to allow the very best expansion in the cavity During installation, the expanding arms swing open and press onto the reverse side of the board The HM can be installed using installation pliers If using a battery operated screwdriver or screwdriver for installation, the preassembled screws must be removed first When screwing in and expanding the fixing, the attachment, or a max 6 mm plate, needs to be used as a turning stop