2PCS 1/8" 1/4" 3/8" 1/2" Female To Male BSP Connector Brass Reducing Adaptor. 6-100mm Diamond Core Hole Saw Hole Cutter Tile Porcelain Glass Drill Bit Cutter. It can convert coaxial or optical digital audio signals into left and right channel analog audio signals, and connect an external device, such as a loudspeaker, through L/R analog audio interface.
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