What are knuckle couplings?

You will find knuckle couplings on American model railways and European ones as this is the standard coupling for everywhere except England.

The knuckle coupling was invented in the late 1800s and is used all over the world today on the prototypes. And goes to show it is as good today as it was when it was first invented.

The knuckle coupling works like a butcher's grip:  if you form both of your hands in to a "C" shape rotate your left hand 180 degrees and place all of your fingers tips together and pull, you will get the idea.

Knuckle couplings are available in model form: in HO scale from Kadee and from Dapol in N gauge.