Feature: 1. SMALL BUT POWERFUL: The Bluetooth amplifier stands out for its compact size and high energy output. The amplifier has a maximum output of 10W plus 10W when paired with 8 ohm speakers and a peak output of 20W plus 20W when paired with 4 ohm speakers. 2. MULTIPLE INPUT METHODS: It has multiple input methods such as Bluetooth input, 3.5mm AUX input, USB input and so on. It is compatible with most devices, such as cell phones, tablets, laptops, MP3 players and so on. You can switch your favorite sound input method at any time. 3. APP CONTROL: In order to realize the maximum potential of this amplifier, we have developed an app for it. You can set the amplifier's Bluetooth name and password through this app. 4. MULTIFUNCTIONAL KNOB DESIGN: You can change the number of times you press the knob to perform corresponding operations, such as switching songs, switching input modes, activating and deactivating APP, and restoring factory mode. 5. PROTECTIVE FEATURES: The power amplifier is equipped with various protective mechanisms to ensure its safe work, such as short circuit prevention, overcurrent prevention, overheating prevention and anti reverse prevention. Specification: Item Type: Bluetooth Power Amplifier Material: Aluminum Alloy Bluetooth: 5.1 Supply Voltage: 9-24V Support: Bluetooth AUX USB Number Of Channels: Left And Right Dual Channels Output Power: 20W Plus 20W Special Features: Support APP Control, Modify Bluetooth Name, Set Bluetooth Password, Turn Off Turn On Tone Protective Mechanism: Overvoltage, Undervoltage, Overheating, Short Circuit Remote Control Battery Specification: 1xCR2025 (Excluded). Package List: 1 x Bluetooth Power Amplifier1 x Sound Cable1 x Cable1 x Remote Control