Monster E129

Monster Open Ear BC300 Swimming Headphones User Manual

Model: E129

Introduction

Thank you for choosing the Monster Open Ear BC300 Swimming Headphones. These bone conduction headphones are designed for comfort and versatility, offering both Bluetooth connectivity and an integrated MP3 player with 32GB storage. With an IPX8 waterproof rating, they are suitable for various activities, including swimming, running, and cycling, allowing you to stay aware of your surroundings while enjoying your audio.

Package Contents

  • Monster Open Ear BC300 Swimming Headphones
  • Magnetic Charging Cable
  • User Manual

Product Overview

Familiarize yourself with the components and controls of your BC300 headphones.

Monster BC300 headphones showing overall design

Image: The Monster BC300 headphones, showcasing their open-ear design and flexible neckband.

Controls and Indicators:

  • Power/Multi-function Button: Power on/off, Play/Pause, Answer/End calls.
  • Volume Up (+): Increase volume, Next track (long press).
  • Volume Down (-): Decrease volume, Previous track (long press).
  • Mode Switch Button: Toggle between Bluetooth mode and MP3 mode.
  • Magnetic Charging Port: For charging and data transfer.
  • LED Indicator: Displays power, charging, and connection status.

Setup

1. Charging the Headphones

Before first use, fully charge your headphones.

  1. Connect the magnetic charging cable to the charging port on the headphones.
  2. Connect the other end of the cable to a USB power adapter (not included) or a computer's USB port.
  3. The LED indicator will show charging status (e.g., red while charging, blue when fully charged).
  4. A full charge takes approximately 2 hours and provides up to 10 hours of playback.
Monster BC300 headphones connected to a laptop via magnetic charging cable

Image: The Monster BC300 headphones connected to a laptop via its magnetic charging cable, illustrating the charging process and data transfer capability.

2. Powering On/Off

  • Power On: Press and hold the Power/Multi-function button for 3 seconds until the LED indicator flashes blue.
  • Power Off: Press and hold the Power/Multi-function button for 5 seconds until the LED indicator flashes red and then turns off.

3. Bluetooth Pairing

Pair your headphones with a Bluetooth-enabled device.

  1. Ensure the headphones are powered off.
  2. Press and hold the Power/Multi-function button for 5-7 seconds until the LED indicator flashes red and blue alternately, indicating pairing mode.
  3. On your device (smartphone, tablet, computer), enable Bluetooth and search for available devices.
  4. Select "Monster BC300" from the list.
  5. Once paired, the LED indicator will flash blue slowly.

4. Using MP3 Mode (Internal Storage)

The headphones have 32GB of internal storage for music playback without a connected device.

Transferring Music Files:

  1. Connect the headphones to your computer using the magnetic charging cable.
  2. The headphones will appear as a removable disk drive on your computer.
  3. Drag and drop your desired audio files (e.g., MP3 format) into the headphone's storage folder.
  4. Safely eject the device from your computer before disconnecting the cable.

Switching to MP3 Mode:

  • While the headphones are powered on, press the Mode Switch button to toggle between Bluetooth and MP3 modes.
  • A voice prompt will indicate the current mode.
  • Note: MP3 mode is recommended for underwater use as Bluetooth signals do not transmit effectively through water.

Operating Instructions

Basic Controls:

FunctionAction
Power On/OffPress and hold Power button (3s for On, 5s for Off)
Play/PauseShort press Power button
Volume UpShort press '+' button
Volume DownShort press '-' button
Next TrackLong press '+' button
Previous TrackLong press '-' button
Answer/End CallShort press Power button
Reject CallLong press Power button
Switch Mode (Bluetooth/MP3)Short press Mode Switch button

Wearing the Headphones

Place the headphones with the transducers resting on your cheekbones, just in front of your ears. The neckband should rest comfortably behind your head.

Person wearing Monster BC300 headphones during a basketball game

Image: A person wearing the Monster BC300 headphones during a basketball game, demonstrating the secure and comfortable fit during physical activity.

Person wearing Monster BC300 headphones while cycling with a helmet

Image: A person wearing the Monster BC300 headphones while cycling, showing how they fit comfortably with a helmet, maintaining open awareness of surroundings.

Underwater Use (IPX8 Waterproof)

The BC300 headphones are IPX8 rated, suitable for submersion up to 2 meters for 2 hours.

  • Always switch to MP3 mode before entering water. Bluetooth signals do not transmit effectively underwater.
  • Ensure the magnetic charging port is clean and dry before and after use to prevent corrosion.
  • Rinse the headphones with fresh water after swimming in chlorinated or saltwater, then dry thoroughly.
Person swimming underwater wearing Monster BC300 headphones and goggles

Image: A person swimming underwater while wearing the Monster BC300 headphones and goggles, demonstrating their IPX8 waterproof capability for aquatic activities.

Maintenance

  • Cleaning: Wipe the headphones with a soft, damp cloth. Do not use harsh chemicals or abrasive cleaners.
  • Drying: After exposure to water, especially after swimming, ensure the headphones are completely dry before charging or connecting to a computer. Gently shake off excess water and wipe with a dry cloth.
  • Storage: Store the headphones in a cool, dry place away from direct sunlight and extreme temperatures.
  • Charging Port: Keep the magnetic charging contacts clean and free of debris to ensure proper charging and data transfer.

Troubleshooting

ProblemPossible Solution
Headphones won't power on.Charge the headphones fully. Ensure the Power button is pressed and held for 3 seconds.
Cannot pair via Bluetooth.Ensure headphones are in pairing mode (flashing red/blue). Turn off and on Bluetooth on your device. Move closer to the device.
No sound in Bluetooth mode.Check volume levels on both headphones and connected device. Ensure headphones are correctly paired. Try re-pairing.
No sound in MP3 mode.Ensure headphones are switched to MP3 mode. Check if music files are properly loaded onto the internal storage. Adjust volume.
Headphones not recognized by computer.Ensure the magnetic charging cable is securely connected. Try a different USB port or cable. Ensure headphones are powered on.
Poor sound quality underwater.Ensure you are using MP3 mode for underwater listening. Bluetooth is not effective underwater.

Specifications

  • Model: E129
  • Brand: Monster
  • Connectivity: Bluetooth 6.0
  • Bluetooth Range: 10 Meters
  • Internal Storage: 32GB (up to 8,000 songs)
  • Water Resistance: IPX8 (submersible up to 2 meters for 2 hours)
  • Battery Life: Up to 10 hours playback
  • Charging Time: Approximately 2 hours
  • Charging Type: Magnetic Charging
  • Ear Placement: Over Ear (Open Ear design)
  • Audio Driver Type: Bone Conduction Driver
  • Audio Driver Size: 13 Millimeters
  • Control Type: Button Control
  • Parcel Dimensions: 15.7 x 11.99 x 5.69 cm
  • Weight: 191 g

Warranty Information

The Monster Open Ear BC300 Swimming Headphones come with a 1-Year Warranty from the date of purchase. This warranty covers manufacturing defects and workmanship under normal use. It does not cover damage caused by misuse, accidents, unauthorized modifications, or normal wear and tear. Please retain your proof of purchase for warranty claims.

Support

For further assistance, technical support, or warranty inquiries, please contact Monster customer service through their official website or the retailer where you purchased the product. Please have your model number (E129) and proof of purchase ready.

You can visit the official Monster store for more information: Monster Official Store

© 2026 Monster. All rights reserved.

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