A Tape with Versatility
Originally developed for heating, ventilation and air conditioning (HVAC) applications, duct tape is used today in a variety of maintenance, repair and construction settings. 3M™ Heavy Duty Duct Tape 3939 is an excellent choice for general indoor application in MRO and construction. The tape was tested for flame spread using test method UL723, ASTM E84 and can be used at temperatures as high as 200°F for up to 30 minutes. The sturdy cloth-reinforced tape can be torn from the roll by hand and sticks instantly, providing a wide range of convenient solutions. This tape has a classic silver-colored backing.
Recommended Applications
- Patching
- Bundling
- Reinforcing
- Tabbing
- Taping / splicing insulation
- Capping pipe
- Securing conduit ends
- Marking
- Labeling
- Temporary repair
- Hanging poly (polyethylene drapes)
- Protecting against light sandblast overspray
Built to Stick
3M’s family of rugged cloth and duct tapes adheres to most surfaces for applications ranging from bundling to moisture proofing, sealing to splicing, reinforcing to hanging poly drapes. Available in a variety of colors and strengths, they’re known best for their hand tearability, high tensile strength and conformability.

3M 33349, 641WY 1/4" X 24", 220 Mesh Diamond Cloth Belt, 7010534919
Dynabrade 40320 Dynafile II Abrasive Belt Tool
3M 08008, Black Super Weatherstrip and Gasket Adhesive, 5 fl oz, 7000045523, 6 per case
3M 22395, Roloc Disc 361F, 60 YF-weight, TR, 3 in, Die R300V, 7000045098
3M 85563, Heavy Duty Duct Tape 3939, Silver, 96 mm x 54.8 m, 9.0 mil, 7100022015
Dynabrade 51632 .1 hp Straight-Line Pencil Grinder, Central Vacuum, 1/8" Collet
Dynabrade 51750 .1 hp Straight-Line Extension Pencil Grinder, Rear Exhaust, 60,000 RPM, 1/8" Collet
3M 33439, Cubitron II File Belt, 33439, 60+, 10 mm x 330 mm (3/8 in x 13 in), 7100033194, 10 belts per carton, 5 cartons per case
3M 14895, Cloth Belt 777F, 80 YF-weight, 1 in x 42 in, Film-lok, Single-flex, 7010299926, 200 per case
Dynabrade 51301 .5 hp Straight-Line Die Grinder
3M 19077, E-A-R, Soft FX Probed Test Plugs 393-2004-50, 50 EA/Case, 7000052883
Dynabrade 13509 Dynastraight Finishing Tool, Rear Exhaust, 6,000 RPM, 5/8" (16 mm) or 1" (25 mm) Dia. Arbor
3M 57173, Temflex Cotton Friction Tape 1755, 3/4 in x 60 ft, Black, 7000058870
3M 16151, PTFE Glass Cloth Tape 5451, Brown, 3/4 in x 36 yd, 5.6 mil, 7000050135
ACS Diamond Cloth Belt, CX1250 3/8" X 24" 75U 
