Note: Please allow some error due to manual measurement. Specification: Item Type: Headphone Amplifier_x000D_Material: Metal_x000D_Input: 2 x XLR_x000D_Output: 3.5mm_x000D_Battery Specification: 9V Battery (Not Included)_x000D_Size: Approx. 10x8.8x3.5cm / 3.9x3.5x1.4in Features: 1PROFESSIONAL DESIGN: Mini headphone amplifier is designed for individual monitoring applications. With volume and balance control knobs. 2DUAL XLR INPUTS: Stereo headphone amplifier with dual XLR inputs, allowing dual mono or stereo operation. 3MIXING FUNCTION: Portable headphone amplifier is designed with mix function, switchable stereo, mono operation. 43.5 MM HEADPHONE OUTPUT: Headphone amplifier features a 3.5mm headphone output with integrated current limiting to protect your ears and headphones. 5NO DISTORTION: Studio headphone amplifier outputs louder, clearer and more vivid stereo sound without distortion. PackageList: 1 x_x000D__x000D_HeadphoneAmplifier 1 x Mounting Adapter 2 x Screws 1 x User Manual