Function: battery display, call function, support music
Bluetooth protocol: 5.0
Channel: stereo
How to use: earplug type
Single or dual ear: bilateral stereo

Use quick guide:

Please note: Song switch/play/pause/answer call/reject call/key support voice assistant activation.

Bluetooth name: X21S
Turn on/off the power: 1. Take out/return to the charging box
2. Long press for 3 seconds to turn on, 5 seconds to turn off

Call: when answering an incoming call, short press to answer the call, long press (3 seconds) to reject
Voice assistant wake up: long press for 2 seconds to activate the voice assistant

Music: Press for 1 second to play/press to pause for 3 seconds to play the next song.

Turn on the red and blue flashing lights, press alternately twice to switch between Chinese and English instructions