The Spika Electronic Earmuff is designed to provide ultimate safety and ear protection against loud noises that may be harmful to the human ear. This earmuff while always providing protection will also amplify low level noises through a speaker built into the headphone itself. Low profile ear cups fit securely to your ear to reduce interference with stocks while aiming. The Spika Electronic Earmuff will amplify noises under 85db while sounds over 85db will be suppressed within a 0.01 second reaction time.