A typical galley is illustrated Fig. 13.3. As a normal uplift of a 747-400 comprises over 40 000 items, stowage is a major function of all galleys. To facilitate this stowage, and subsequent delivery of products to passengers, a system of trolleys or carts form basis of the service system. Such trolleys are loaded with food and other customer requisites by the supplying outlet, and the trolleys are then transported to the aircraft and stored in special insert bays in the galleys. The trolleys are subsequently removed from these bays by the cabin crew. This cuts down the amount handling of the food and beverage items. Other storage containers support the trolleys, and they too are located in special compartments within the galleys. Some equipment, such as sinks, water boilers and ovens, may be permanently installed, but in other cases a airline may choose to adopt a modular system which will give some potential flexibility of use.