Sensors (IMAGE) University of California - San Diego Caption Researchers spent four years perfecting the recipe for the sensors' materials. Sensors designed to work on a subject's hair are made of a mix of silver and carbon deposited on a flexible substrate. This material allows sensors to remain flexible and durable while still conducting high-quality signals--a silver/silver-chloride coating is key here. Credit Jacobs School of Engineering/UC San Diego Usage Restrictions Please credit Jacobs School of Engineering/UC San Diego 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.