The first cars for the "L" to feature sliding doors, the 2400-series also features smooth steel exteriors, ideal for decals and, in many cases, advertisements. As delivered, the cars featured a red, white, and blue color scheme on the front and rear of the cars, as well as stripes along the sides. These were modified several times over the years and the colors were eventually removed from all cars, leaving them unpainted to match the bare stainless steel scheme of the rest of the fleet. Some cars feature advertising and cars 2401–2422 are work cars which are identified by red and white striping along their sides as well as on the front and rear of the cars. (Cars 2423-2424 were converted to work cars some time after 2401-2422 had been converted.)