Vox VGH-Bass Amplifier Headphone; Dynamic, closed-back headphones with integrated, analog bass amp technology; Direct connection to electric bass, without any additional preamplifier; Quality drivers from Audio-Technica; Powerful sound with high dynamic range; Integrated effects; Battery operation for unlimited mobility; Discreet design in elegant black; 1,6m dimensioned cable ensures optimum comfort, even when playing standing up; Easily accessible switches and controls; Driver diameter: 40 mm; sound level: 97 dB; Frequency range: 20 Hz to 20,000 Hz; AUX IN jack for connecting music players or other audio sources; Controls Gain, Tone, Volume, Effect, Standby; Inputs: jack plug (6.3mm stereo jack), AUX IN jack (3.5mm mini stereo jack); Power supply: 2 x AAA battery 8 hours (manganese) / 20 hours (alkali); (W x D x H ) 195 x 160 x 50mm; Weight 230 g (without batteries); Supplied with 2 x AAA battery for function test; Maximum input level 1,000 mV.