XY-ST21PRO Compact 2.1Channel TPA3255 BT Digital Power Amplifier Board High And Low Tone Subwoofer Power Amplifier Board 100W*2+200W Type: without case, with case, with line (optional) Main color: black PowerSupply: DC12-30Volt/5A above BT: 5.2 Audio input: BT+AUX+U Disk+USB Sound Card BT audio decoding: AAC/SBC U disk decoding: WAV/FLAC/APE/MP3 Left and right channel output power: 10W+10W@8Ω/12VDC 20W+20W@4Ω/12VDC 35W+35W@8Ω/24VDC 70W+70W@4Ω/24VDC 60W+60W@8Ω/30VDC 100W+100W@4Ω/30VDC Subwoofer output power: 10W @8Ω/12VDC 20W @4Ω/12VDC 35W @8Ω/24VDC 70W @4Ω/24VDC 60W @8Ω/30VDC 100W @4Ω/30VDC 200W @2Ω/30VDC Without case size: 111 * 100 * 23mm / 4.4 * 3.9 * 0.9in With case size: 112 * 102 * 28mm / 4.4 * 4.0 * 1.1in Package size: 150 * 132 * 53mm / 5.9 * 5.2 * 2.1in Package weight: without case: 255g / 9.0ounce with case: 345g / 12.2ounce with line: 295g / 10.4ounce