Most of you knew this. I only learned all the details recently. So here goes. American lenses, like a majority of Americans, are bulbous. In other words, fat, over stuffed, wide girth. European lenses, like a shrinking majority of Europeans, are svelte, thin and sleek. Euros come in three varieties, all amber, all clear, and half amber and half clear. Depending, I believe, on the country the coupe landed in.