Wall plug Fischer DuoHM 4 x 55 S PH PZ Grey 4 mm Diameter 55 mm Length

Fischer DuoHM wall plug (4 x 55 S PH PZ) is a cavity anchor designed to secure attachments in panel building materials with thicknesses from 9.5 to 30 mm. The plug combines a nylon base body and a metal sleeve to form a reliable anchor for M4 screws; the delivered set includes plugs and matching screws. Its narrow edge keeps the fixing hidden behind the mounted part, and the metric internal thread allows repeated screwing and unscrewing.

Advantages

The DuoHM installs quickly and easily with a cordless screwdriver without additional setting tools, cutting installation time by up to 50% versus conventional panel plugs. Its two-component construction—metal sleeve and nylon base—provides high load capacity: the metal sleeve folds and presses against the back of the panel while the nylon body knots in the material. One plug length covers common panel thicknesses from 9.5–30 mm for flexible and cost-efficient use. A nylon anti-rotation lock prevents rotation during installation and protects the surface of the building material. The metric internal thread allows the screw to be removed and refitted multiple times, and the plug accepts standard metric screws in addition to the supplied ones.

Suitable for

• Mounting fixtures to plasterboard, gypsum fibreboard and other panel building materials
• Fixing light to medium-weight items where panel thickness is 9.5–30 mm
• Applications requiring repeated removal and reinstallation of screws (M4)

Key specifications

• Brand: FISCHER
• Model: DuoHM 4 x 55 S PH PZ
• Diameter: 4 mm
• Length: 55 mm
• Suitable screw size: M4 (metric internal thread)
• Suitable panel thickness: 9.5–30 mm
• Material: Nylon base body with metal sleeve
• Colour: Grey
• Package contents: 25 wall plugs and screws (as supplied)
• MPN: 572920
• EAN: 4048962523980

How to use

Drill a hole to the plug diameter, insert the Fischer DuoHM plug into the panel until the narrow edge sits flush, then drive the supplied M4 screw with a compatible PH or PZ bit using a cordless screwdriver. The metal sleeve will fold and clamp against the rear of the panel while the nylon body forms a knot in the material. To remove the attachment, unscrew the screw; the metric internal thread allows multiple reinsertions of the screw. If required, you may use other standard M4 screws compatible with the plug.

Usage recommendations

Use the DuoHM plug only in appropriate panel building materials within the specified thickness range (9.5–30 mm) and with M4 screws. For optimum performance, follow drilling diameter and installation depth recommendations and avoid using the plug in unsuitable base materials such as solid masonry.