3M Aluminum Foil Tape 3340, 2.5" x 50 yd, 4.0 mil, Silver, HVAC, Sealing and Patching Hot and Cold Air Ducts, Fiberglass Duct Board, Insulation, Metal Repair

This is the best tape we've ever used! Very sticky and stays on!

Works and sticks good sealing duct frame for filters. USN came out with duct tape, submarines would use it to stick problem people to ceilings (no joke)

This is the good one, this stuff is tough too. I always like to have some on hand for projects around the house. You’d be surprised how useful this tape can be once you have some on hand. My dad always used this at work (HVAC) so I’ve learned over the years how to properly use this tape to make my A/C more efficient. This is great for taping up cracks around your furnace or condenser coil. You can also use it to tape the chill line near the outside unit if your lines have areas that are exposed, or if there are places that are beginning to be exposed. You can buy cheaper brands, but there’s some things you shouldn’t buy off brand, and this one of them. Buy the legit 3M tape, it’s worth it. It’ll save you money in the long run as you won’t constantly be having to patch up previous applications. I’m not a certified HVAC tech, but after riding with my dad from elementary school until I graduated, I do know to highly recommend this specific tape. This can also be used on small windows, such as the small window panes on some front/back doors, and for lots of other applications. If you’re a homeowner, I truly believe a roll of this tape should be in your home tool box.

Great tape! Unfortunately received dirty and not as described from seller! I use this tape all the time…best tape for my needs! This item was Described as "Looks and functions as if it were new. Item will come in original packaging.” sold by Amazon.com Services, Inc. Unfortunately it was not in it’s original packaging…and a plastic bag over it. It was also dirty. I will keep it and use it anyway. Wish the description was more accurate…I paid too much for the condition I received!

Purchased for A/C ducts in the attic, the insulation was torn and falling off. This seems to be top quality tape, very sticky, cuts with heavy duty scissors or shears, a little pricy, but you get what you pay for! All the other 3M products I purchased have been of top quality! I most likely will need a second roll of tape to really secure the duck work, it even looks good and professional, words often not used when I do a job!

Used this to make repairs my HVAC guy missed. Super easy to use and seals around ventilation system. Every homeowner should have a roll of this.

I have been doing heating and air conditioning with going to school over 30 years ago. Yes, you will find much aluminum tape that is less expensive on Amazon for sure. I have always used this with it being made by 3M knowing how good it is and would say out of all different aluminum tapes. I’ve used this is 10 times better than any other tape I ever used. Surprises me it’s not much more expensive with how unbelievable it really is and if you purchase it versus cheaper ones, you know by the odor of the adhesive that is on it. Other stuff I’ve used did not only stick the greatest. Yes it’s stuck on any ductwork. I put it on this made by 3M. Wow. Even if you do not do HVAC for a living and need aluminum tape, this is beyond your best choice believe me.

VERY strong and reliable (3M). I trust this brand!

Ninguna otra cinta había podido funcionar con el tubo del aire acodicinado; colocamos esta y ya lleva algunos días sin que se caiga.

Selling fake Product in the name of 3M Returned and again received same product.

This foil tape is easier to work with them most of the other stuff. Great product would highly recommend it.

This is thick foil tape with a high temperature acrylic adhesive designed for sealing attic bathroom exhaust hoses etc with prominent code compliance labeling. It has a much stronger smell than other foil tapes I have used--definitely more of a pro class product and 0.5” wider than common foil tapes as well. Due to its thickness, it is also less conformable than what is ideal for average furnace and duct seam sealing purposes. I prefer thinner general purpose foil tapes in that role (Climaloc, Nashua 322, 3M 3311 etc). This does provide an added layer of protection for applying to sharp irregular surfaces as it does not tear easily, but it is also thick enough for its edges to cut you if you aren't careful.

I use this on clean, oil free duct work. Yes this is an expensive foil tape (cheaper if you buy it by the case) but the cold weather tack is effective and the adhesion will last for years even with the temperature cycles. I prefer the the thicker tapes (this is one of them) and 3M uses a quality adhesive. Tack is when the tape is first applied (TO A CLEAN SURFACE) and adheres to the surface. Adhesion is the ability to remain attached to the surface for a length of time and through temperature cycles. Flagging is the tape releasing from the surface (Adhesion has failed) and with the cheap tapes this happens in a few years. This is a pressure sensitive tape and MUST be smoothed down with an applicator and NOT just your hand. I believe in doing a job once and to the best of my ability and this tape has met my expectations