Subwoofer Sponge Plug: high-density sponges and speaker tube sponges are to fit reflex port sizes, ensuring a tailored solution for any speaker box or subwoofer. The reflex port plug fits seamlessly into the speaker tube, decreasing unwanted humming and boosting bass reflex efficiency.Experience improved bass performance using the subwoofer port plug, which doubles as a sound absorbing pad for speakers and a cabinet bass plug.
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