[Mr 5 0]

All 'cat-back' means is that the exhaust system has been replaced from the catalytic converters 'back', which would include the connector pipes (from the catalytic converter to the muffler), the mufflers and the tailpipes. In short, you replaced the exhaust system. Few people have to replace the catalytic converters and in fact, many Mustang owners remove them and replace them with a pipe that leads to the headers.

Your photo shows that you still have the catalytic converters, new connector pipes, new mufflers and, I would presume, new tailpipes. I presume this because the old tailpipes are usually rusted at the muffler connection and impossible to save. Besides, every knowledgable Mustang owner wants the bright, shiny exhaust tips that new stainless steel tailpipes offer.

I trust this explains the definition of 'cat-back' exhaust and reassures you that is exactly what you have.