One of the world's leading manufacturers of heavy-vehicle axles is Kirkstall Forge Engineering of Leeds, a member of the GKN Group. Kirkstall operates a forge division in which special components are produced from billets weighing up to 1200 lb. The associated machine shop has kept pace with developments and includes several CNC turning machines and other modern production units. One of the latest machine tools to be installed is a Herbert vertical Ultrafin machine for the rough and finish boring and facing of rear axle banjo units. Built at the Herbert Lutterworth plant, the machine can handle six different sizes of workpiece, requiring six interchangeable boring heads, although all have the same basic configuration. Weight of the workpieces varies between 300 and 350 lb.