The HP-1 is a belt-worn; battery-powered headphone amplifier that brings excellent performance to portable applications. With a locking 1/4/XLR Combo input jack, sturdy belt clip, and output volume control, it provides reliable performance both on and off the stage. The HP-1 provides a high output level when used with a variety of different headphones and is great for in-ear monitoring applications. Its long battery life will not leave you stranded. The HP-1 is packaged in a rugged extrusion, with heavy-duty jacks for years of reliable operation.Main Features:High Output Headphone AmplifierLocking /XLR Combo Input JackBalanced Mono/ Unbalanced Stereo SwitchVariable Volume ControlSturdy Belt ClipOver 40hrs from 2 AA Batteries3.5mm Output ConnectorRugged DesignSpecifications:Input Connections: Locking /XLR combo jackInput Impedance: 5K OhmsMax Input level: +6.6dBuOutput Connections: 3.5mm Jack (1/8)Gain: +9dBTHD: .02% @1kHz typ.Max Output: 105mW @ 0.1% THDTypical run time: 40 hrs. (Alkaline batteries)Power Requirements: 2-AA batteries IncludedDimensions (HxWxD): 5.4×1.72×1.6 (13743.×40.6 mm)Weight: 0.51 lbs. / 0.23kg