1x Low-pass Filter NE5532 Hifi Subwoofer 2.1CH Pre-Amplifier Preamp Board. (D) Dual-panel design, and strive to simple signal transmission, signal to noise ratio is very high. (G) PCB ultra-hardness FR-4 fiberglass board, board size: 82x30mm, excluding protruding parts, thickness: 1.6mm.
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