The amplified microphone is a great way to observe sound waves on an oscilloscope. The output level is much higher than the traditional crystal microphones giving a very clear trace. Two amplified microphones can be used with a storage oscilloscope or Motion QED to measure the speed of sound.Specification:Battery: 3 x AAA (not supplied)Gain: 125Frequency range: 0 - 20kHzOutput :± 2V a.c.There are no leads included with the amplified microphone.Standard laboratory leads with 4mm connectors are compatible.To use with an Oscilloscope, a 4mm to BNC Connector is required (sold separately - B8R06754)