"A more rugged and reliable Shunting device have we never seen!" The SAFETRACK® SafeShunt™ Track Circuit Shunts or Short Circuit Device is a very safe shunting device used to block a track section of the railway track circuits to give a "stop" condition to oncoming train. This to protect work teams or avoid collisions between oncoming trains and obstacles on the track.The SafeShunt™ simulates the presence of a train.