Bluetooth hearing protection (up to two devices at the same time) for phone calls and music. The perfect hearing protector for those who depend on constant telephone communication in their work. Synergy offers clear voice quality during calls, even in the noisiest environments. Active listening microphones on each earpiece ensure excellent directional hearing, provide natural sounds, and enable you to hear conversations, warning signs and other important information without compromising on your protection. They include AM/FM radio in the headphones themselves and are compatible with smart phone voice assistants.