Manufactured in the late 1940's to the early 1950’s this vintage Auricon NRS24-A7 is a Sound On Film Recording Amplifier. This unit appears to be in very good condition. Unfortunately, I don't have the batteries to be able to test it properly. For those interested in converting the amplifier for use with AC, there are instructions that can easily be found online. Included are the travel case and output cable for connecting the amplifier to the camera.