The MTX Thunder 421D Mono Subwoofer Amplifier is a powerful and reliable audio component designed for car audio systems. With its mono channels, this amplifier is perfect for delivering deep and immersive bass sound to your vehicle's audio system. The MTX brand is known for its quality products, and the Thunder421D model is sure to impress with its performance and durability. Although untested, this amplifier is a great choice for audiophiles looking to enhance their car audio experience. UNTESTED
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