Fully Peltor compatible. Separate volume controls for driver and codriver. Relies directly on vehicle's 12 volt power. Noise cancelling microphone for unequalled clarity and sound quality. Radio connection with on/off switch. AVC (Auto Volume Control) system elminiates 100% of amplified ambient noise. Innovative limiter avoids noise spikes. Audio output for connecting a camera or MP3 recording device. Audio input for connecting an MP3 player.