Adhesive Metal Tape 3M 431, Soft Aluminium Carrier, 12 mm x 55 m

3M 431 Adhesive Metal Tape with a soft aluminium carrier, 12 mm x 55 m, is a narrow, conformable metal tape designed for sealing, patching and shielding tasks. The soft aluminium backing allows the tape to follow curved or irregular surfaces while the pressure-sensitive adhesive provides immediate tack and reliable adhesion to metal, plastic-coated surfaces and many common building materials. Its compact width makes it suitable for precision applications where a slim, flexible metal tape is needed.

Advantages

The soft aluminium carrier provides good conformability and can be formed around seams and small-diameter ducts without creasing. A pressure-sensitive adhesive offers quick application and secure bonding without the need for heat activation. The narrow 12 mm width enables accurate placement in tight spaces and on irregular surfaces. The tape resists corrosion and helps maintain electrical continuity where metal coverage and shielding are required.

Suitable for

• Sealing joints and seams in HVAC ducts and fittings
• Patching small holes, punctures and tears in metal or coated surfaces
• Electrical shielding and continuity repairs on metal enclosures
• General repair work and light metalwork where a flexible aluminium tape is required

Key specifications

• Material: soft aluminium carrier with pressure-sensitive adhesive
• Width: 12 mm
• Length: 55 m
• Backing thickness: thin, conformable aluminium (manufacturer typical)
• Adhesive type: pressure-sensitive for immediate tack
• Surface compatibility: metal, coated metal, many plastics and building materials

How to use

Ensure surfaces are clean, dry and free of dust, oil or loose material before application. Cut the required length of tape and press the adhesive side firmly onto the substrate, smoothing from the center outward to remove air pockets and achieve good contact. For curved or irregular surfaces, form the tape gradually to conform to shapes and apply additional pressure along edges. Overlap adjacent pieces by a small margin when sealing seams to maintain continuous coverage.

Usage recommendations

Store the roll in a cool, dry place out of direct sunlight. For long-term outdoor exposure or high-temperature environments, verify suitability for the specific application and consider using a tape specified for outdoor durability. Test adhesion on an inconspicuous area if surface compatibility is unknown.