Fischer DuoHM 4x55 S PH PZ Hollow Wall Anchor 55 mm 4 Pieces 572911

For electricians and drywall installers mounting light fixtures, cable conduits, or bathroom accessories on plasterboard, the Fischer DuoHM 4x55 S PH PZ hollow wall anchor delivers a secure hold without the need for a setting tool. Its zinc-plated steel construction resists corrosion, while the anti-rotation feature prevents spinning during installation. Pre-positioned installation means you drill the 8 mm hole, push the anchor through, and drive the 4 mm screw—no fumbling behind the panel.

Key specifications

• Anchor type: Hollow wall anchor
• Material: Zinc-plated steel
• Anchor length: 55 mm
• Screw diameter: 4 mm
• Screw length: 55 mm
• Drill hole diameter: 8 mm
• Minimum cavity depth: 55 mm
• Panel thickness range: 3 - 12 mm
• Drive type: PH2 / PZ2 combination head
• Installation type: Pre-positioned
• Anti-rotation feature: Yes
• Pack quantity: 4 pieces
• Product series: Fischer DuoHM

Why choose it

The DuoHM's unique design allows the screw to be removed and reinserted without losing grip, making it ideal for temporary fixtures or maintenance access. The combination head accepts both Phillips and Pozidriv bits, reducing the need for multiple screwdrivers on site. Zinc plating ensures long-term reliability in indoor environments, even in humid areas like bathrooms.

Ideal use cases

• Mounting light switches and sockets on drywall
• Securing curtain rails and blinds
• Installing lightweight shelves and mirrors
• Fastening cable trays and conduit clips
• Attaching bathroom accessories like towel rails

Good to know

For best results, ensure the cavity depth is at least 55 mm and the panel thickness is between 3 and 12 mm. Use an 8 mm drill bit for the hole. The anchor is suitable for plasterboard, gypsum fibreboard, and light building boards. Each pack contains 4 anchors with matching screws.