Last number redialing after connecting with your phone, double click the power button to redial your latest calling record. Pairing tips: First time to pair: 1.Long press the power button for 7 seconds until red&blue light flashes alternatively and you can hear "power on, pairing " to enter the pairing model, 2.Start your Bluetooth function on the phone, 3.Search for the device name"mxb, touch it to connect with earphone, only blue light will flashes and you can hear "connected ", device connected successfully. Pairing it second time: 1.Following the above step 1 to enter the pairing model, 2.Start your Bluetooth function on the phone, 3.Find "mxb**" in paired device history record list and touch it to connect successfully. Warm tips for users charging the headset before first usage for 2 hours, charge it more than 2 hours will hurt the battery. Charge connector: Pc/laptop, support 5v 500mah-1a charger only. Warning: Not use power bank. The 5v 2a charger, over voltage earphone can't be charged normally. Specifications: Bluetooth version: V4.1+edr Bluetooth profiles supported: Hsp, hfp, a2dp, avrcp operation range: Up to 10 meters battery: Built-in rechargeable 3.7v/60mah lithium battery charge voltage: Dc4.75-5.25v charging time: Approx. 2 hours playing time: Up to 3.5 hours talk time : Up to 5 hours standby time : Up to 180 hours package include: 1 Bluetooth headset 1 charging cable1 pairs of silicone ear caps 1 users manual.