When it is hot, it always feels cooler when air is moving. This is the principle behind the Breezer's design. It transfers fresh air from the outside cooling down your pet. Very similar to sitting in front of a fan but because it takes in outside air, it cools your pet's house faster as the daily temperature drops. The unit is made from steel, powder coated to a beautiful mat finish. It is thermostatically controlled but since it "sips" electricity, it can run all summer for pennies per month. It transfers outside air into the house at a rate of 24 cubic feet per minute. That is more than one air exchange per minute!! It does this at a noise level of less than 45 decibels. It provides a very soothing "white noise" that, in test trials, actually curbs barking! The cyclonic style fan is rated at 30,000+ hours so it will last for many years. The unit (shown here) also comes with a heavily wrapped stainless steel spring to help deter the worst chewers. I have included all necessary hardware, including a 5" hole saw, screws and pictured directions, to make installation easy and fast.