Bluetooth 5.2, supports serial port name change (refer to HY5066TWS module user manual), supports one-click TWS pairing, supports AUX connection to TWS case without disconnection, powers on automatically, supports hands-free calling, default volume is maximum, with volume synchronization TX, RX, GND: TTL serial port configuration 9600, N, 8, 1 At 24V 4A, maximum output power is 2×50W; at 19V 4A, maximum output power is 2×40W; 8–24V power supply, with reverse polarity protection, compatible with laptop power adapters After TWS pairing, the connection persists across power cycles LED indicator: After TWS setup, single board LED stays on and outputs left channel only; dual board LED blinks and outputs stereo sound Color: As shown Material: Plastic Function buttons: P/V–: Short press for next track; long press to decrease volume N/V+: Short press for previous track; long press to increase volume PLAY: Short press to play/pause Double-click to toggle ShareMe mode (audio channel switches automatically in loop after TWS setup) Stereo channel assignment: right–left–stereo Press and hold for 3 seconds to reject or re-pair phone (host device only) TWS: Short press for one-button TWS pairing Double-click to cycle through EQ modes (9-band EQ) Press and hold for 3 seconds and release to confirm action with audible prompt Press and hold for 6 seconds to clear pairing history and reset EQ to default Minor variations in appearance and labeling may occur between production batches; these do not affect functionality Package Contents: 1 × Development Board Note: Color appearance may vary slightly due to lighting conditions and screen settings. Measurement tolerance: ±1–3 cm.