SHOKZ OpenFit Open-Ear True Wireless Earbuds (Black) - Manual (Page 18)

Both earbuds support independent use for mono music or
calls. When used alone, the earbud retains the function of
its current button. (Refer to music control on Page 11 and
call control on Page 12)
SINGLE EARBUD CONTROL
Single Earbud Control
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