Towards the end of its life as a common backshop type setter, the Ludlow was often joined by the "Super Surfacer" a specially designed surface plane that would smooth the surface of the freshly cast type and ensure it was exactly type high. A Ludlow slug was just the letters overhanging a central spine about 12 points wide (T shaped viewed from the end). It needed to be bolstered by Elrod slugs on either side for support. The number of slugs above and below the central spine could adjust the white space above and below the type making it a very flexible system for large type.