The new SRC-System™ is a communication system integrated into the accoustic collar. Following the plug & play principle, it is inserted into your helmet within minutes | Article: Schuberth SRC System C3 / C3 Basic / E1 Communication System, black, Size 2XS XS S M L | Article: Schuberth SRC System C3 / C3 Basic / E1 Communication System, black, Size 2XS XS S M L, black, Size 2XS XS S M L