TURN MONO INTO FULL STEREO: With TWS function, pair two ZK-1001U boards wirelessly to create a true left-right stereo system. No complicated wiring, no extra receivers—just pure, wide soundstage from two compact amps. Perfect for DIY stereo builds or upgrading old mono speakers. HIFI AMP WITH INDEPENDENT BASS & TREBLE TUNING: Driven by the TPA3116D2 chip, this portable mono amplifier board delivers rich, detailed sound with ultra-low distortion (