Features: Stereoed effect: Supports 2.1 channel output, providing richer audioed levels and stereoed experience. Powerful bass: By modifying the subwoofer, a deep and strong bass effect can be achieved, allowing users to enjoy a stunning music and audioed experiences. Wide power input range: suitable for AC12-15V power supply, compatible for various power devices, convenient for use and installation. Multifunctional mixing board: supports adjusting and optimizing audioed signals, including adjusting parameters such as volume, timbre, and bass, to meet the unique needs of users. Quality sound processing: Using quality audioed processing chips to ensure the stability and fidelities of audioed signal transmission and processing, restoring more realistic music details. Easy modification: It can be used as a tuning board for modifying subwoofers, making it convenient for users to upgraded and improve the sound quality of existing subwoofers. Specifications: Material: Printed Circuit Board Size: Approx. 15cm/5.91inch(more detail size please refer to pictures) Model: BY-2100 Working Vlotage: Double AC12V-15V Channel: 2.1 Channel Operational Amplifier Type: 5532 Package Includes: 1 Piece BY-2100 2.1 Channel Tuning Amplifier Board note: The output speaker wire should not be short circuited, otherwise it will burn out the amplifier tube. Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.