NO BATTERY COMES WITH IT JUST TO SHOW IT WORKS AND TO COMPARE SIZE OF RELAY THIS CAME FROM A RELATIVE OF THE ESTATE WHO WORKED AT CHATTANOOGA AND NEW YORK FOR THE RR IN THE EARLY 60s AS SHOWN WORKS I PUT 9VDC TO IT QUICKLY SO NOT TO HURT IT IF VOLTAGE WAS TO HIGH IT WORKED W.U. Tel. Co. Signal Relay 4 Ohm Telegraph 3 C Works Good Shape For Age Used THANKS JERRY HOMBASE GB2