The bright color of SARTs enables their quick detection, whereas the combination of transmitter and receiver enables it to transmit as well as receive radio signals. SART machines have been instrumental in rescuing several crafts and ships by reacting to the search signal sent from an X-band radar, typically of 9 GHz. These signals are known as homing signals. The response is usually displayed on radar screens as a sequence of dots on a X band-radar, which helps rescuers reach the vessels in time.
A SART is basically an electronic device that automatically reacts to the emission or interrogation by radar. This enhances the visibility of the party in need of assistance on the radar display (PPI). They operate on the 9 GHz band and only transmit, when they are switched on, when interrogated by a radar.