Adhesive Tape 3M Weichaluminium 425, 55 m × 25 mm, aluminium foil adhesive tape

3M Weichaluminium 425 is an aluminium foil adhesive tape on a 55 m roll with a 25 mm width designed for sealing, surface protection and heat reflection. The metal-backed construction offers conformability to irregular shapes and reliable adhesion on HVAC ducts, insulation seams and patch repairs. The thin foil carrier allows the tape to follow contours while providing a metallic barrier against heat and moisture.

Advantages

The tape combines a flexible aluminium foil carrier with an aggressive pressure-sensitive adhesive to ensure secure bonding on metal, painted surfaces and many common building materials. Its narrow 25 mm width makes it easy to apply in tight spaces and along seams, while the 55 m length reduces the need for frequent roll changes. The metal backing offers thermal reflectivity and a durable surface that resists tearing during conforming and installation.

Suitable for

• Sealing HVAC ducts and fittings
• Patching insulation joints and seams
• Surface protection during fabrication or transport
• Small repairs on metal surfaces and conduit
• Applications requiring a metal-backed adhesive barrier

Key specifications

• Carrier: aluminium foil
• Adhesive type: pressure-sensitive adhesive
• Roll length: 55 m
• Width: 25 mm
• Function: sealing, heat reflection, surface protection
• Conformability: suitable for irregular surfaces and contours

How to use

Ensure surfaces are clean, dry and free of dust, oil or loose particles before application. Measure and cut the required length, then press the tape firmly into place along seams or over the area to be sealed. For best adhesion, apply pressure and smooth the tape from the centre outward to remove wrinkles and air pockets. Overlap adjacent strips where continuous coverage is required.

Usage recommendations

The product is intended for general sealing and protection tasks; avoid prolonged exposure to solvents or extremely high temperatures beyond the tape's specified limits. Store rolls in a cool, dry place away from direct sunlight and apply at moderate ambient temperatures for optimal bond performance.