Photos showing the coupling in action.

 

The wagons uncoupled, A on the left, B on the right.

The wagons are pushed together, the loop on A passing over the hook on B.

The loop on A strikes the dropper on B and this raises the hook until the pin is attracted and held by the magnet.

The loco reverses and tensions the couplings. As the hook on B is raised it is caught by the loop on A. This stretching action pulls the magnet from the pin and would allow the hook to drop but it is it is prevented from doing this by the loop on A. The wagons are coupled

To uncouple, the loco moves the wagons together until the hook on B drops. This occurs as the magnet and pin are separated and gravity allows the hook to drop. The loco is stopped at this moment.

The wagons are now uncoupled.

If you wish to uncouple the 2nd, 3rd or other wagon in a rake, as the wagons move together, they uncouple then recouple. Stop the movement at the time the hook drops at the place you wish to uncouple and reverse the movement.