This 1919 Chevrolet "Copper-Cooled" was GM's first air-cooled production vehicle. The copper-cooled engine, developed at GM's Research Labs, utilized finned copper sleeves around each cylinder to replace the normal water jacket cooling system. Unfortunately, the copper fins worked better in the lab than they did on the road. After a short production run, the Copper-Cooled engines were replaced with a conventional water-cooled engine. The copper-cooled engines were later sold successfully as stationary engines for industrial pumping systems.