So today my dad was driving and suddenly a banging noise under the car. When he checked he noticed this object (see pic) hooked on to the tray under the car. Once removed there was no knocks or rattles and every thing seems okay but he is left wondering is it just debris  been picked up or has it fallen off the car which we both think unlikely as it looks older and looks manually twisted. Can't recall seeing this before. He has a 2023 Fiesta mk 8.5 trend with only 4000 miles on it so we think it's unlikely to be off the car.  Anybody got any thoughts what it might be ?  I thought possibly an old wheel trim ring.

Well, I agree with the wheel trim prognosis, based on the bend half way up.

Other ideas are welcome.

Thanks. 2 points now for the wheel trim ring.

 

Yes, it's the retaining ring from a plastic hub cap.

Thanks.

As others have said or even - a wire coat hanger! I once had one of these wrap itself around my foot, jamming into the pedals and the end sticking into my ankle while pedalling a bike in traffic - what fun (not)