Refrigeration is one of mankind’s greatest inventions—so much so that it seems impossible to improve upon. But that’s just what LG has done with their newest appliance, the InstaView refrigerator.

The InstaView addresses a common refrigerator problem. We have all opened the fridge to see what’s in there, but standing there with the door open allows refrigerated air and energy to escape, which is bad news for the environment and your energy bill. The InstaView solves this issue with a tinted panel on the right door that becomes translucent when someone knocks on it twice. Knock knock, voila—you can view the contents of your refrigerator and save the coolness for inside, where it belongs.

The LG InstaView isn’t the first fridge with translucent panel technology—Haier has a motion sensor model with panels that fade to transparency when users approached and dimmed when they walked away, and LG itself has a “Signature” fridge with a knock-to-transparency feature—both the InstaView is the first one available in the United States. It also features a door-in-door compartment, which allows users to access the contents like a snack or a drink stored in the door without opening the entire fridge—another energy-saving innovation. The four-door model will be priced at $4,500 and the three-door model at $4,300. The InstaView is expected to be available for purchase this coming fall.