You can measure it if you want real numbers for that particular horn trumpet. May be 2X the draw of a 6V. But that's OK because the internal wires are 6V big and the diaphragm is metal, so not much can happen unless horn button sticks. If you are worried, run it thru a ballast resistor and add a fuse.


Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn