Hollow construction dowel FISCHER DuoHM 5x55 S PH TX, pack of 4

Hollow construction dowel FISCHER DuoHM 5x55 S PH TX, pack of 4 is a combined sleeve-and-screw anchor designed for secure fixing in hollow building materials. The 5x55 mm dimensions make it suitable for medium-duty interior attachments where the substrate has cavities or hollow cores. The PH/TX drive head provides straightforward tightening and reliable engagement for installations such as light shelving, conduit clamps and sanitary fittings.

Advantages

The DuoHM system integrates a composite sleeve and a matched screw to create a stable connection in hollow substrates. Its design distributes loads across the sleeve to reduce point stress on fragile materials while the screw drive ensures defined torque transmission. The compact 5x55 size accommodates common inner-wall cavity depths and the included PH/TX head improves installation speed with standard bits. Supplied as a pack of four, it is convenient for small projects and replacements.

Suitable for

• Mounting light shelves and small cabinets to hollow walls
• Securing conduit clips, cable trays and electrical boxes in hollow substrates
• Fixing sanitary fittings, towel rails and small brackets to partition walls

When it may not be suitable

This dowel is intended for hollow or cavity building materials and for medium-duty loads; it may not be suitable for solid masonry such as concrete or full brick where different anchor types are preferred. For heavy structural loads, large appliances or safety-critical attachments, a high-capacity anchor system or mechanical fixings designed for the specific substrate should be chosen.

Key specifications

• Anchor type: hollow construction sleeve with matched screw
• Size: 5 x 55 mm (diameter x length)
• Drive type: combined Philips / Torx (PH TX)
• Material: composite sleeve with metal screw
• Pack contents: 4 complete anchors

How to use

Drill a hole matching the 5 mm diameter recommendation, clean the hole of dust and position the dowel so the sleeve sits flush with the surface. Insert the screw and tighten with a compatible Philips or Torx bit until the sleeve expands or folds to engage the hollow cavity. Tighten to a steady torque appropriate for the substrate and the fixture; avoid overtightening which can deform the sleeve or damage the hollow material.

What to consider before purchase

• Confirm the substrate is hollow or has a cavity suitable for a hollow-wall anchor
• Check required load capacity for your fixture and choose an anchor rated for that load
• Ensure you have the correct drill bit and a compatible PH/TX driver bit

Usage recommendations

Use the DuoHM 5x55 S PH TX for light to medium interior fixings in plasterboard, hollow block and similar hollow wall constructions. Always follow recommended drill diameters and mounting instructions for reliable performance and check each fixing after installation for secure engagement.