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3M™ Foil Tape 3340 Silver, 2-1/2 in x 50 yd 4.0 mil, 9 rolls per case

3M ID  70006658481    UPC#  00051111078112    3M Product Number  3340     
3M(TM) Foil Tape 3340 UL181A-P Roll Image
3M(TM) Foil Tape 3340 UL181A-P Roll Image
3M™ Foil Tape 3340 is ideal for sealing rigid fiberglass duct boards and flexible (non-metallic) air duct and connector systems. Our tape meets requirements for UL 181 A-P and UL 181 B-FX Listings as a measure of reliability and quality standards.
  • Conformable tape resists flame, moisture, weather, UV degradation, and many chemicals
  • 2.0 aluminum foil backing is ideal as a vapor seal tape for duct closure
  • Thermally conductive backing helps heating and cooling efficiency
  • Heat and light reflective tape protects insulates and enhances lighting efficiency
  • Permanent acrylic adhesive combined with the durable 2.0 mil backing provides long service life
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We constructed this tape using a 2.0 mil aluminum foil backing with strong, pressure sensitive acrylic adhesive for long-term adhesion along with a paper liner to protect the adhesive and keep the tape ready for use. This tape has excellent heat and light reflection to protect against high temperatures and U.V. degradation. It is also flame, moisture, weather, and chemical resistant. The combination of the foil backing and acrylic adhesive gives our tape an operational temperature range of -300 to 2500F/-340 to 1210C.

The foil backing also serves as an excellent barrier against moisture, dust, flame, and many chemicals. Its very low moisture vapor transmission rate also makes the tape a good sealant.

The acrylic adhesive supplies superior temperature, U.V. and solvent resistance to give you a strong, lasting and reliable bond. It provides excellent age life and is ideal for long-term indoor and outdoor environments.


 Adhesion to Steel oz/in (N/100 mm)‎‎ 30 (33)
 Adhesive Type‎‎ Acrylic
 Applications‎‎ Sealing HVAC & Duct Work
 Backing Material‎‎ Aluminum Foil
 Backing Thickness‎‎ 2 mil
 Backing Thickness (metric)‎‎ 0.05 mm
 Brand‎‎ 3M
 Color‎‎ Silver
 Industries‎‎ Transportation,‎ Specialty Vehicle,‎ Metalworking,‎ Construction,‎ Automotive,‎ Military & Government,‎ General Industrial,‎ MRO,‎ Electronics,‎ Aerospace
 Length‎‎ 50 Linear Yard
 Length (Metric)‎‎ 45.72 m
 Liner Type‎‎ Paper
 Maximum Operating Temperature (Celsius)‎‎ 121 Degree Celsius
 Maximum Operating Temperature (Fahrenheit)‎‎ 250 Degree Fahrenheit
 Meets Specifications‎‎ UL 181A-P,‎ UL 181B-FX
 Operating Temperature Range (Celsius)‎‎ -34 to 121 Degree Celsius
 Operating Temperature Range (Fahrenheit)‎‎ -30 to 250 Degree Fahrenheit
 Product Form‎‎ Roll
 Tensile Strength‎‎ 20 lb/in
 Tensile Strength (metric)‎‎ 350 N/100mm
 Total Thickness‎‎ 4 mil
 Width‎‎ 2.5 Inch
 Width (Metric)‎‎ 63.5 mm