Power plug size: 55X2.1mm. Amplifier and power The amplifier is designed to be powered from a 12V power supply. Controls and interface Control buttons include: power switch, bass adjustment, volume adjustment, treble adjustment. Ondevice tone controls allow quick sound shaping without external equipment. Speakers and matching Product matching: a pair of 26 inch passive speakers. Compatibility and connections Supports connection to mobile phones, computers, MP3 players, and set boxes. Key benefits and why you would use it Simple ondevice tone control lets you tailor bass and treble to suit your room and content. Compatibility with common devices enables versatile use with phones, computers, players, and set boxes. Large 26 inch passive speakers offer strong sound projection when paired with an appropriate amplifier and power supply. 12V power compatibility supports compact, portable, or integrated setups suitable for various environments. Straightforward setup and operation with minimal components. Use scenarios Desktop computer or laptop use: connect to a computer or phone for clearer music, videos, or conferencing audio. Living room or home theater: pair with a compatible amplifier and source device (such as a set box) for enhanced TV or streaming audio. Small classroom or event space: provide audible background music or presentations by connecting to a suitable 12V powered amplifier.