ADEL in Place (IMAGE) U.S. National Science Foundation Caption The ADEL(TM), which looks like a tiny ear-sealing balloon, is a sacrificial membrane that disrupts excessive pressure waves, protecting the ear drum when in-ear listening devices are used. Credit Zina Deretsky, NSF; Asius Usage Restrictions Must credit NSF License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.