Portable USB DAC Headphone Amplifier - Grey (X1) 64 position analog volume control Plays All Music Files: MP3 to 24-bit/96kHz Variable output drives powered speakers or power amp Direct-coupled circuitry from the ESS Sabre DAC 9023 chip through the analog volume control and analog output section This Product Has 12 Months Replacement Warranty. We focus on providing quality power products and excellent customer service.