Retro windows are the most common one that we do for installation. We remove the glass of the window, we remove the frame but we don't disturb the wood. We don't disturb the drywall. We don't disturb the stucco. And then after installation, we add a hundred percent silicone P- 600 - a commercial grade silicone. You can't even buy that, you have to be licensed to order one. You have to have a glazing license to buy it. Our next common one would be a block frame. Usually block frame is for wood windows. You’d want to keep the aesthetics of the wood trim on it. You would seal that on the wood side so the window can only be removed from the inside. There’s a ton of other choices, just give us a call and we’ll let you know which window best fits your home.