1[HiFi BT Chip] This sound amplifier is equipped with HiFi Bluetooth chip and external antenna for long distance Bluetooth reception, tested to achieve over 50 meters. 2[Powerful Amplification] With 20dB gain, this sound amplifier can drive various sound amplifiers, high impedance and low impedance earphones effortlessly. 3[Sound Allocation] Featuring three sets of interfaces for simultaneous output, including two sets of phono connectors and a 3.5mm headphone jack, provides flexibility. 4[Sound Mixing] The 3.5mm input interface can work simultaneously with Bluetooth sound, allowing for mixed sound output, enhancing the versatility and functionality of this amplifier. 5[Flexible Power Supply] Power supply: DC512V, working current: 5V 220mA, 12V 85mA, this sound preamplifier can be powered by a 12V power adapter, power bank, or a phone charger. 1 xBluetoothSoundAmplifier 1 x Antenna 1 x Data Cable