This is the expandable tube from the air cleaner to the exhaust manifold cover to aid in cold start up. In the parts book they call it connector, a/cleaner to exhaust manifold heat tube. I believe each (1) part need to be cut to fit, and there is actually enough for 2 uses or cars.
The part # I have is 3577808 which started in use in 71, but the "fits all models" part # of 3462462 (1970) superseded to this as early as July 9 1973 (the earliest supersession book I personally have showing the change up) so it is a correct replacement part for your 70 up Mopar, whatever it is...Cuda GTX Dart Charger Truck 300 etc. As you can see, it is the correct black with tan inside, NOT the pep boys silver crap. Roughly 2 feet long, compressed.
I have not seen any of these for sale for years.