Features - Color: Black. - Size: 8.8 x 9.3 x 4.6 cm. - Material: Metal. - USB Input: 5V. - Power supply voltage: 48V. - Use the isolated voltage-boosting technology to effectively prevent the ground signal interference. - Use the built-in low-pass filter circuit design to fully filter out the interference noise from the external audio equipment. - Use soft-start function to avoid the impulsive sound of puff when booting the device. - Use two sets of balanced power supply to balance the input and output signals makes the voltage be balanced and stable and inhibit common mode interference. - Use the USB-5V voltage boost circuit and the low-voltage power supply technology to prevent harm to the human body to settle the mismatch problems among the different regional electric supplies voltages and transformers.