Headset DEFENDER FREEMOTION B571 LED wireless binaural, 4 cm drivers, 6–8 h battery, closed acoustic, 20–20000 Hz

The Defender FREEMOTION B571 LED headset provides flexible wired and wireless connectivity with Bluetooth, suitable for calls, music playback, sports use and everyday listening. With a frequency response of 20–20000 Hz and a wireless range of up to 10 meters, the headphones deliver a full audio spectrum for voice and media. The supra-aural ear coupling and adjustable head-band design aim to balance comfort and stability while the lightweight construction of approximately 200 grams supports longer wear without excessive pressure.

Advantages

These grey headphones combine wired and wireless modes in one device, allowing users to switch between Bluetooth and a cable connection as needed. The wide frequency range covers low, mid and high frequencies suitable for speech and general music genres. The supra-aural ear pads and head-band wearing style provide a stable fit for active use, while the modest weight reduces strain during extended sessions. Integrated LED elements offer a simple visual accent without affecting primary audio performance.

Suitable for

• Voice and video calls — mobile and desktop communication
• Listening to music and podcasts at home or on the go
• Light sports and fitness activities where on-ear stability is required
• Everyday commuting and travel within the Bluetooth range

Key specifications

• Connectivity: wired and wireless (Bluetooth)
• Frequency range: 20–20000 Hz
• Wireless range: up to 10 meters
• Ear coupling: supra-aural (on-ear)
• Wearing style: adjustable head-band
• Weight: approximately 0.2 kg
• Colour: grey

How to use

For wireless operation, enable Bluetooth on your source device, put the headset into pairing mode as described in the quick start guide, and select the device name from the list of available devices. For wired use, connect the supplied audio cable to the headset and to the audio output of your device. Wear the headset by placing the ear pads over the ears and adjusting the head-band for a secure, comfortable fit. Adjust volume and call controls using the on-device buttons where available.

Recommendations

Use the wired connection when Bluetooth is not available or to conserve headset battery. Keep the device within the specified wireless range for stable audio and minimal latency. Clean the ear pads occasionally with a dry or slightly damp cloth and store the headset in a protective case to prolong component life.