Light-Weight and Sweat Proof. As light as 18 grams. Never a burden to the ears. Rubber coating is comfortable to touch and wear, soft and skin friendly. With ergonomical design, ear hooks and rotatable earbuds makes the headsets fit your ear perfectly.Along with their rubber coating, these headsets hardly cause foreign body sensation when wearing. Friction been reduced to minimum on condition that the earbuds can fit in ears firmly when doing sports. The Most Advanced Bluetooth 4.1 Chips Hardware Configuration Ensure Hi-Fi CD Qual llows devices to reconnect automatically when they are in proximity of one another. Hands free calling: Built-in Microphone. Picking up and hanging up phone calls. In standby mode, double-click the MF button, can redial your last call. Simple to use: Press and hold headphones’ power button for approximately 8 seconds and let go until you see the blue/red alternating lights. The headset is now in pairing mode.