5Copyright © 2005 Nokia. All rights reserved.1. IntroductionRead this user guide carefully before using the headset. Read also the user guidefor your phone, which provides important safety and maintenance information.Keep the headset out of reach of small children.The Nokia Bluetooth headset HS-37W is designed for all-day wear, and providesup to 15 hours of talk time with a single AAA battery.This device is intended for use when supplied with power from a 1.5 V LR03 / AAAAlkaline battery. The use of any other types may invalidate any approval orwarranty, and may be dangerous. Always switch the device off before removingthe battery. Ensure the correct polarity is observed when inserting the battery.Do not try to recharge the battery unless the manufacturer of the battery hasintended the battery to be rechargeable.■ Bluetooth wireless technologyThe HS-37W headset can be connected to a compatible mobile phone thatsupports Bluetooth wireless technology. The Bluetooth wireless technology makesit possible to connect compatible communication devices without cables. ABluetooth connection does not require that the phone and the headset be in lineof sight, but both devices should be within 10 meters of each other. Connectionscan be subject to interference from obstructions, such as walls, or other electronicdevices.