Plastic outer window
Is none too thick; a good whack would probably crack it. The inner window is heavy glass and is built into the seal for the door; that's why it doesn't leak. We have the same model in our showroom at THD. Some LG models have the plastic and some have just the inner glass. I took a look at the one on our floor and it seems like you can replace the door with just a phillips' head. No idea of replacement cost, but you can contact LG at 800-984-7469.