A7 TWS Wireless Bluetooth Headset Stereo Handfree Sports Bluetooth Earphone With Charging Box For iphone Android PK X2T i7/i7s Color:black Size Chart(Unit:cm/inch) Size:2XL Waist:84cm/33

Size Chart(Unit:cm/inch) Size:2XL Waist:84cm/33

(3) Bluetooth usage frequency: 24Ghz

Tops Type:Tees

Uppers:Flyknit Fabric

Feature: Waterproof

A7 TWS Wireless Bluetooth Headset Stereo Handfree Sports Bluetooth Earphone With Charging Box For iphone Android PK X2T i7/i7s Color:black Size Chart(Unit:cm/inch) Size:2XL Waist:84cm/33note: there is a film to protect the case from scrach during the transportion! it is not scratch!!! the 1 step: take out two earphone ,press both switch for 6 seconds to let go ,until the two headphone indicator light flash red and blue,wait for 3 seconds, double click any one of earphones switch(the main headsets) then two headphone in series with each other,at this point,master headphone showes flashing blue and red,vice headphones shows slow flash