Features: Adopts original TPA3123 and TL074 are used. Ffront input capacitors and coupling capacitors adopt top capacitors1UF. Main filter capacitors adopt 2×1000UF capacitors, which ensures strong and constant support. Resistors selection of precise chip resistors to ensure a signal-to-noise ratios. Adopt 1.6mm thick double side plate, full process, to ensure that size of current through a good performances. Use fully enclosed dustproof potentiometer, more stable performances, than ordinary potentiometer! Specifications: Item: TPA3123 2.1CH Digital amplifier board Power: DC12-24V Power: 2X25W+50W subwoofer Line board size: 82x65MM/3.23x2.56in Package Includes: 1PCS TPA3123 2.1CH Digital amplifier board note: Due to the problem of lighting effects and shooting, there will be tolerances in the product, please understand. Please allow 0-1cm error due to the manual measurment