Mechanics Engine Diagnostic Stethoscope Tool Sonarscope Sound Noise Detector Mechanic Listening Tool Set Kit

This device helped me find the failed alternator bearing in my car. Without the extension, it works quite well. However, the extension fits poorly and reduces the transmission of the noise up the shaft to the ear pieces. Use it without the extension if you can.My mediocre rating on comfort is because these things are never comfortable on me, I wear a size 8 hat.