Fischer DuoHM 6x55 S Cavity Anchor with Screws, 4 Pieces 572913

When mounting shelves or bathroom accessories onto plasterboard walls, a standard plug often fails to hold. The Fischer DuoHM 6x55 S cavity anchor solves this by expanding behind the board, creating a secure form-fitting grip in hollow materials. Each pack contains four zinc-plated steel anchors with matching Phillips/Pozi screws, ready for immediate use.

Key specifications

• Anchor diameter: 6 mm
• Anchor length: 55 mm
• Drill hole diameter: 6 mm
• Minimum cavity depth: 50 mm
• Maximum fixture thickness: 10 mm
• Material: zinc-plated steel
• Suitable for plasterboard, gypsum fibreboard, light building boards, hollow bricks
• Includes 4 screws with Phillips (PH2) and Pozi (PZ2) drive

Why choose it

The DuoHM anchor is engineered for hollow walls where traditional plugs cannot grip. Its pre-positioned installation allows you to set the anchor through the fixture, then drive the screw to expand the wings behind the board. The galvanized coating provides corrosion resistance, making it suitable for indoor use in dry or occasionally damp areas. The flange head prevents the anchor from pulling through the board, ensuring a neat finish.

Ideal use cases

• Mounting lightweight shelves, curtain rods, and picture frames on plasterboard
• Securing bathroom accessories like towel rails and small cabinets on gypsum fibreboard
• Installing light fixtures and cable conduits on hollow bricks or light building boards
• Fastening brackets and hooks in drywall partitions

Good to know

For best results, drill a 6 mm hole and ensure the cavity depth is at least 50 mm. The anchor is installed through the fixture (pre-positioned), so no separate marking is needed. Use a PH2 or PZ2 screwdriver bit to drive the screw until the wings expand and the head is flush. Each pack includes 4 anchors and 4 screws.