Features: This product features a classic two-stage tone with low distortion and wide adjustment ranges. Treble and bass are independently adjustable. The power interface is the standard 5.5x2.1mm power jack base. Supports Bluetooth-compatible connection. Whether you're setting up a home theater or creating a personal listening experience, this amplifier board delivers exceptional sound quality and precise tone adjustment. Specifications: Material: Metal Bluetooth-compatible Version: 5.0 (no shielding, 15 meters) SNR: > 90dB Input: AUX+ Bluetooth-compatible Channel: 2 (stereo) Power Supply: DC9~24V/3A or higher (Do not connect to 24V battery pack) Adapter Speaker: 15~100W, 4~8Ω Power Supply Voltage: 12V-----8Ω/12W+12W, 4Ω/20W+20W, 15V-----8Ω/18W+18W, 4Ω/30W+30W, 19V-----8Ω/30W+30W, 4Ω/40W+40W , 24V-----8Ω/40W+40W, 4Ω/50W+50W Protection Mechanism: Overheating, Overcurrent, Short Circuit Protection Length: Approx. 8.9cm/3.5'' Note: Please allow 1mm errors due to manual measurement. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package Includes: 1x Power Amplifier