Sony WF-1000XM4 Black Earphone Left Side (L) Only *The battery has deteriorated and can only play for about 5 minutes, so this is a junk item. As this is a used item, there may be small scratches and dirt that cannot be removed. Please understand that this is a junk item for parts and consider purchasing it. --Regarding Pairing Method-- How to Initialize With the headset in the charging case and the lid open, touch and hold both the L and R touch sensors for about 10 seconds. Release your fingers when the headset's lamp (red) starts flashing. The lamp (green) will flash 4 times, and the headset will be initialized and returned to factory settings, deleting all device registration (pairing) information. After that, you can pair and use it. Search Keywords #WH-1000XM