Vox AC30 Sound Guitar Headphone, Headphone Preamp for Electric Guitar, Dynamic, closed headphones with integrated analogue guitar amp technology, Direct connection to the electric guitar, without additional preamp, Quality drivers by Audio-Technica, Powerful sound with high dynamic range, Integrated effects, Battery operation for unlimited mobility, 1.6 m connecting cable for optimal comfort, even when playing standing up, Easy-access switches and controls, Driver diameter: 40 mm, Output sound pressure: 97 dB, Maximum input level: 1,000 mV, Frequency range: 20 - 20,000 Hz, Controls: Gain, Tone, Volume, Effect, Standby, Input: jack plug (6.3 mm stereo jack), AUX IN jack 3.5 mm stereo for connecting music players or other audio sources, Power supply: 2 AAA batteries 7 hours (manganese) / 16 hours (alkaline), Dimensions (W x D x H ): 195 x 160 x 50 mm, Weight: 230 g (without batteries), Colour: Black, Includes 2 AAA batteries for function test