Some common factors for Necklace fan quality control:
Appearance
Quantity check
Measurement(weight & size & thickness)
Basic function check
Working hours after battery fully charged
Charge time(from 0% ~ 100%)
Rub test
360 degrees adjustable
Internal check
Button test switch and 7 colors
Application check
DB check
RPM
3M tape test for Logo
Barcode scanning
Carton dropping test