A bone conduction device, comprising: a sound input element configured to receive an acoustic sound signal one or more functional components, wherein at least one of said one or more functional components is an electronics module configured to generate an electrical signal representing said acoustic sound signal and a transducer configured to generate motion of a mass component based on said electrical signal so as to generate one or more mechanical forces resulting in one or more of motion and vibration of a recipients skull thereby causing sound perception, wherein said mass component comprises at least one of said one or more functional components.