LG HBS-910 Tone Infinim Bluetooth Stereo Headset (Certified Refurbished) (Silver) Quad-Layer Speaker Technology - balanced audio and less distortion .To comply with the FCC RF exposure compliance requirements, no change to the antenna or the device is permitted. Any change to the antenna or the device could result in the device exceeding the RF exposure requirements and void the users authority to operate the device. . This Certified Refurbished product is tested and certified to look and work like new. The refurbishing process includes functionality testing, basic cleaning, inspection, and repackaging. The product ships with all relevant accessories, a minimum 90-day warranty, and may arrive in a generic box. Only select sellers who maintain a high performance bar may offer Certified Refurbished products on Amazon.com . Retractable Ear Buds - an intuitive wire management solution with a comfortable, customizable fit .This Bluetooth headset and the electronic device connected to the headset operate using radio signals, mobile and landline networks as well as user-programmed functions, which cannot guarantee connection under all conditions. Therefore you should never rely solely upon any electronic device for essential communications (e.g. medical emergencies). Remember, in order to make or receive calls, the headset and the electronic device connected to the headset must be switched on and in a service area with adequate mobile signal strength., Dual MEMS Microphones - delivers exceptional voice call clarity for uninterrupted conversations.The sound is low - Control the sound level of the device connected to the HBS-910.Harman Kardon Signature Sound - refined, full-bodied sound with rich bass Slide and hold the Volume jog switch in the volume down (-) direction for 1 second to check the Indicator lamp and battery level by voice. If the device connected to the product is out of effective communication range (33 feet / 10 meters), the communication signal becomes weak and the communication is lost. If the device comes back within effective communication range, the product automatically reconnects to the device. If the device is not automatically reconnected, press the Call button on the product to connect to it manually. If a device that is not in use goes out of communication range when multiple devices are connected, the product vibrates and a voice message indicates that the connection is lost. In this case, the automatic reconnection function is not supported.