The ELT (Emergency Locator Transmitter) is located behind the rear bulkhead. It is set to transmit a signal of it's location if the airplane comes to an abrupt stop. It can also be removed and used to transmit voice. Now it is connected to the antenna just behind the rear windows but if it is removed from the airplane another antenna, strapped on top of it, is to be used. Chances are this transmitter will never be used. Along that line, I store a medical kit behind my seat. Also there is a fire extinguisher between the seats. Here is a photo of the medical kit and the ELT behind the removed rear bulkhead.
Notice the cables on the left side of the photo. They operate the rudder and elevators. The white wire that goes down from the ELT connects it to a panel mounted console that will tell me if the ELT is transmitting. It could go off because of a hard landing. The other two wires near the ELT goes to the lights on the tail.