The device is made using Shrinky Dinks – plastic sheets that shrink to a fraction of their original size when heated. They are popular among children because they can be coloured and cut into shapes before shrinking. … It could be a useful tool for monitoring people with chronic lung conditions, such as asthma and cystic fibrosis, says Michelle Khine at the University of California, Irvine, who led the team. People will use the device by sticking it to their lower ribs.