A subcategory C1 vehicle with a maximum authorised mass of at least 4000 kg, with a length of at least 5 m and capable of a speed of at least 80 km/h; fitted with anti-lock brakes and equipped with recording equipment as defined by Regulation (EEC) No 3821/85; the cargo compartment shall consist of a closed box body which is at least as wide and as high as the cab.