All Neoteck Product Comes With 18 Months US Base WarrantyOverview:HiFi Headphone Amplifier, Delicate, Compact, Lightweight, and, Which Make it Convenient to Carry, Can Output Remarkable Sound without Distortion.Features:Small Compact Audio Stereo Headphone Amplifier is Convenient and Easy to Use3.5mm AUX Input and OutputHigh Quality Audio, Suitable for MP3 MP4 Mobile Phone Laptop PCNoise Reduction Function, and Distortion with Enhanced Dynamics, Perfect Pure Stereo Effect, HD Voice Music Sound Quality OptimizationAluminum Matte Surface, Give You a Sturdy FeelingBuilt-in Rechargeble Battery, Charge by Micro USB CablePower LED and Charge LED Indicator SupportedSpecifications:Input/Output Port: 3.5mm Audio InputLithium Battery Capacity: 2000mAHAmp Using Time: More Than 8 HoursAmp Internal Voltage: 8.3V/1ASNR>100DbTHD+N 0.0003%Output Power: 40Mw in Impedance 16Adapted Headphone Impedance: 10-150Dimension: 97 x 60 x 15(L x W x H)Package Included:1 x Headphone Amplifier1 x USB Power Cable1 x Audio Cable1 x User Manual