Typically weighing 25 long tons (25,000 kg) when loaded with 3,000 imperial gallons (3,603 US gal; 13,638 L) of milk product, it resulted in a wagon that was as heavy as an express passenger coach. Formed into specialised milk trains, to reduce time delays to market they were hauled by topline express locomotives, including Kings, Castles and Halls, unlike the similarly heavy coal trains.