The cords, two flexible bands of muscle lined with delicate tissue called mucosae, resonate in response to energy from the airflow. (sciencemag.org)
You can also do some weight training with weight stacks like plates with cables and pulleys with flexible bands or rods. (healthandfitnessvitality.com)
It accommodates both semi-flexible and fully flexible bands and charges your Apple Watch vertically or horizontally. (pocket-lint.com)