Sony WF-1000XM4 Auriculares o Estuche de Repuesto - Izquierda Derecha O Estuche --FIRMWARE 2.1.0

If you need firmware 2.0.1 let us know and we will send you one otherwise we will send the 2.1.0. Place the headset in the charging case, leave the lid of the charging case open and wait for lights to flash repeatedly (red) in sets of 3, then hold your fingers to the touch sensors on both the left and right units for about 10 seconds.

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