Field Asymmetric Ion Mobility Spectrometer (FAIMS) is a technique that makes use of mobility transverse to the movement of ions in an MS or MS source.
There are several ways to use this, such as a drift tube, but in FAIMS, use is made of a patented chip technology. The chip itself fits easily onto your fingertips and the flow path is at nano scale.
Due to this miniaturization, it is possible to carry out a second measurement. The separation of isomers or groups of ions is the most widely used technique. There are many applications available and there will be many more to come, because this technology is still very progressive and there are still many unexplored application areas. There are FAIMS resources available for almost all the different MS manufacturers and instruments.