MINNEAPOLIS (WCCO) — We’re testing out another popular “As Seen on TV” product on Tuesday in our “Does it Really Work” series on consumer products.

The “Dual Draft Stopper” goes at the base of a door or window to keep the draft out. It claims to save you energy and money. These are real popular this time of year as it gets colder and we try to save money on our gas and energy bills.

This one we purchased for $8, and here’s what we found. It appears to be a foam tube wrapped with some nylon, and the claim is that it keeps the cold air out and holds the warm air in.

We found a door with a good size gap to test the Dual Draft Stopper. Rick Wheeler with SustainMax, a company that goes into residences and checks for air leaks, helped us out with the inspection of the product.

A blower door was used to create a draft and see how well the weather strip performs under the conditions. An infrared camera and some chemical smoke was used to see if the weather strip actually does hold the warm air in and keep the cold air out.

The Dual Draft Stopper is easy to put in the gap as is slides right under any door. When we blew out a pressure difference to see if air came in, dark streaks could be seen across the floor and up the door. That’s cold air coming into the house.

Wheeler said the equipment seems to work partially but does not do a sufficient job of air sealing. The smoke that got through was seen blowing rapidly away from the door stop.

The next test was to see if we could pull the smoke from outside into the house. A test showed the chemical smoke went around the weather strip.

Wheeler said the device performed about how he thought it would. He said air leakage an represent about 35 percent of your monthly heating bill, and putting something at the point of drafting air is better than nothing at all.

Rick with SustainMax even went as far as saying that you’d get the same result as putting a towel or a blanket in front of a door.

A lot of doors are different sizes, so how do you make sure it fits properly under your door? You can take the foam out and cut it to size the bottom frame of the door.