New from S ' G Tool Aid is their #32100 Electronic Stethoscope to help technicians locate unwanted noises from various leaks, as well as bearing noises, squeaks, rattles, faulty lifters, valve knocks and other sounds. The set comes with a microphone at the end of an 8" flexible shaft to help detect and amplify sound. The unit's headphones also fit comfortably over the ears to help block outside noise. A 9-volt alkaline battery and plastic molded storage case are included.