The Energy Top Damper is a great way to save money on heating costs. In fact, they usually recoup the cost within 1-3 years. It’s a win-win situation. With its soft, pliable rubber gasket, the Energy Top has an air tight “refrigerator” seal. It is attached to the frame and actually compresses and conforms to the lid, forming a strong flexible barrier to the outside elements. No other damper on the market has this type of seal.