4 Inch Insulated Flexible Duct - 4 FT Noise Reducer Heavy-Duty Four Layer Protection Hose, Insulated Duct for Exhaust Fan Insulation, Heating & Cooling Ventilation, Black

Purchased for a portable AC exhaust hose replacement. Works GREAT! Gets barely warm to the touch, when the old exhaust hose was extremely hot and radiating heat back into the room. AC is a little quieter too. Can't recommend this insulated duct highly enough, I can't believe I had been undermining my AC's efficiency for years with a non-insulated exhaust duct. The duct itself feels very well-made, each end has a short length of reinforced foil which fits under the included hose clamps perfectly. Insulated outer duct begins a few inches later, and the outer duct material feels very durable and flexible. The inner duct acts as the support and the outer duct holds the insulation in place, and the result is a dramatic drop in outer duct temp. AC has been running for a few hours now the outer duct is no hotter. I think we have a winner.

The stock hoses for my portable (two-hose!) air conditioner had disintegrated, and I've long been considering buying a set of insulated hoses for it ever since I bought the unit. I'm honestly surprised that they were not insulated at all out of the box. As such, I bought two of these hoses in 6"x8'. Installing them onto the original hose adapters was a bit of a task, entailing very liberal application of duct tape. This done, I connected them up and powered the unit up. I did not buy these hoses with the intent of being quiet, but I was honestly and pleasantly surprised by how much quieter the condenser side fan was now. I can barely hear it anymore, and it quickly subsides under the sound of the compressor once pressure builds. With the original hoses, it was easily the loudest part of the entire air conditioner. I cannot measure the thermal performance directly versus the original hoses, due to the original hoses having disintegrated years ago as of me writing this review. However, I can definitely say that, before, it was actually hot behind the unit. With these, it's significantly cooler, and the unit's performance has significantly improved. It can now actually cool my garage! Something it used to struggle with. The hoses have also survived from a durability standpoint significantly better than the original plastic hoses. Although they ARE a little less convenient to store when the air conditioner's not in use thanks to their bulk. That's the only "negative", other than the admittedly improvised installation, that I can even say about them. Final Answer: If you have a portable air conditioner and use it with any regularity, upgrade it to insulated hose(s) now. You will not regret it.

Excellent item, complies with requirements.

Pros: Overall quality and ease of installation. Insulation is thick. Cons: The inner foil is thin, which made connecting it with the hose clamps a challenge without tearing it. This would hands down be a 5-start if the inner foil were thicker.

I wanted to muffle the sound from an inline fan used for a bathroom - I chose the 8' version to maximize the sound deadening effect even though I only needed a short distance, and it worked perfectly: whisper quiet

We replaced a bathroom ventilation fan located on the ground-floor of a 2-story home. The previous home-owner had installed an un-insulated, plastic, flexible duct to connect the ceiling-mounted vent fan to the exterior wall-exhaust and not only was it incredibly noisy but also inefficient - so much that you could hear the reverberation of the fan in the room directly above the bathroom. After removing the previous duct-run, we measured that approximately 2.5-3 feet of duct was needed to span between the fan exhaust and the exterior wall and this specific duct was perfect as its 4 foot length. The extra length allowed us some slack so that we could maneuver and install it without giving us a headache - since we had to work strictly through the existing hole in the ceiling where the exhaust fan was located our space was very limited. It can be incredibly difficult to source such a short-run of insulated duct for a fair price. This specific insulated duct was a very good value and of good quality. In addition to installing this insulated duct we also re-positioned some of the ceiling insulation since this replacement duct had more 'bulk' than the previous un-insulated plastic duct. If I run into another situation as above I would not hesitate to purchase this insulated duct again.

Super tight fit. I mean you will struggle to get it over the duct.

I needed to remove and replace the inner aluminum duct as it was full of holes. I don’t understand how or why they would want that. I don’t want hot air from my dryer going anywhere but outside. It cost way too much for having to do that rework to it. But it has stopped the condensation issues I had.

Worked great. Feels like quality. Slightly disappointed with the ends. Foil separated but clamped as one pice. Could have been more gentle. 1st time. But workers great for noise reduction.

Work good. Alittle costly. Just a note that the ducting ends will fit 4". But is more like 6" with the paddling around the body. Will not fit a 4" hole But the ends fit 4".

Well made, used for exhaust fan in bathroom. No problem fitting to 4" pipe.

Didn’t need it but was good product

DONT cut it ! Just use whole length and buy multiple if needed don’t try cutting trust me !