The 'X' symbol on the back of the last coach of Indian trains is a crucial symbol in railway safety. It is used to ensure that all the coaches in the train are properly connected. Station masters and railway staff observe this symbol and ensure that the train has arrived safely. If a coach is disconnected and the 'X' symbol is not visible, then they are immediately alerted and other trains are stopped. The 'LV' board on the back of the last coach, radium paint that glows at night, and a blinking red light also enhance safety. This is one of the important rules implemented by Indian Railways for the protection of passengers.