3M 4991 VHB Double-Sided Acrylic Foam Tape (Gray, 2.3mm)

Engineered for demanding industrial and automotive bonding, 3M™ VHB™ Tape 4991 is a heavy-duty, 2.3mm (90 mil) thick double-sided acrylic foam tape. Featuring a highly conformable foam core and multi-purpose acrylic adhesive, it provides extraordinary gap-filling capability and permanent bonding strength across mismatched, textured, or irregular surfaces.

Key Features

• Extreme Bond Strength: Creates a permanent, high-strength seal that effectively replaces mechanical fasteners such as rivets, spot welds, screws, and liquid adhesives.
• Conformable 2.3mm Foam Core: Viscoelastic acrylic foam absorbs vibration, compensates for differential thermal expansion, and fills large gaps on irregular or textured surfaces.
• Broad Substrate Adhesion: Bonds securely to high and medium surface energy materials including metals, glass, painted surfaces, and rigid plastics.
• Weather & Chemical Resistance: Engineered to withstand harsh outdoor conditions, UV radiation, moisture, thermal cycling, and common automotive solvents.

Product Specifications

• Brand & Model: 3M VHB 4991
• Adhesive Family: Multi-Purpose Acrylic Adhesive
• Core Construction: Conformable Acrylic Foam
• Tape Thickness: 2.3 mm (approx. 90 mil, without release liner)
• Color: Gray
• Roll Length: 16.5 Meters (approx. 18 Yards)
• Continuous Operating Temperature: Up to 93°C (200°F)
• Short-Term Heat Resistance: Up to 121°C (250°F)
• Available Widths: 8mm, 10mm, 15mm, 20mm, 25mm

Recommended Applications

• Automotive exterior trim, side moldings, rocker panel claddings, and emblem mounting.
• Architectural cladding, commercial signage, and metal fabrication.
• Industrial equipment panels, electronics housings, and display assembly.
• Textured, rough, or mismatched bonding surfaces requiring superior gap filling.

Application & Bonding Guidelines

• Bond surfaces must be clean, dry, and free of oil or contaminants. Clean thoroughly with a 50:50 mixture of isopropyl alcohol (IPA) and water before application.
• Apply firm pressure (recommended minimum 15 psi / 100 kPa) with a roller to ensure 100% surface contact.
• Bond strength develops progressively at room temperature (approx. 50% after 20 minutes, 90% after 24 hours, and 100% after 72 hours). Ideal application temperature is between 21°C and 38°C (70°F to 100°F).

Custom Slitting & Bulk Orders

We provide custom precision slitting for any specific width and die-cut shapes upon request. Volume discounts are available for commercial and manufacturing projects. Contact us for custom inquiries.