Older stations tend to use a separate pipe for every kind of available fuel and for every dispenser. Newer stations may employ a single pipe for every dispenser. This pipe houses a number of smaller pipes for the individual fuel types. Fuel tanks, dispenser and nozzles used to fill car tanks employ vapor recovery systems, which prevents releases of vapor into the atmosphere with a system of pipes. The exhausts are placed as high as possible. A vapor recovery system may be employed at the exhaust pipe. This system collects the vapors, liquifies them and releases them back into the lowest grade fuel tank available.