STRONG CAMEL Green Electronic Stereo Hearing Ear Protector Earmuff Protection Cut off automatically over 85dB in only 2 millisecond to keep the sound,Amplification 8 times to detect the ambient sounds if lower than 70dB Independent electronic circuit on both cups for better performance Light weight ,cool design,Dual knobs for on/off and volume,Adjustable and soft padded headband Comfortable ear cushion,Powered by 2x1.5v N batteries on each cup over 300 hours lifetime(alkaline) Idea for shooter, hunter and worker involved in noisy surrounding