The invention discloses an earplug which comprises an invisible
handle and an earplug body, a sound
transmission channel is formed in the invisible
handle and the earplug body, a movable block is arranged in the sound
transmission channel and connected with a motor, a circuit board and a control button are arranged on the invisible
handle, and the control button is connected with the movable block. The
noise reduction film in the earplug expands along with the increase of the
noise, so that the
noise is prevented from entering the ear of a user; when a user enters an environment with large noise, the control button can be pressed down, the movable block blocks the sound
transmission channel and controls noise to enter ears of a user, when the
user needs to listen to speak of others, the control button is pressed down again, the motor and / or the driving rod pulls the movable block back to the original position, the sound transmission channel is kept unblocked, and the user can listen tospeaking of others normally; when someone shouts the name of the user, the earphone plays the sound of the shouter to the user, so that the user can reply in time.