Earplugs, small receivers that fit in the ear, commonly used in radios and hearing aids. It can also be plugged in the ear, used to prevent water from entering the ear when swimming, and can also be used to reduce noise interference, that is, anti-noise earplugs, sleep earplugs and other such earplugs are commonly referred to as headphones, which belong to personal audio and are used for Walkman music use. According to the classification of their energy conversion methods, there are mainly moving coil method, moving iron method, electrostatic type and isomagnetic type. It can be classified into semi-open type and closed type according to the structure. In terms of wearing methods, there are flat head type, ear hook type, in-ear type and head-mounted type. It can also be simply divided into earmuffs and earplugs. Labor insurance type noise-proof earplugs are generally made of silicone or low-pressure foam mold material, high-elasticity polyester material. After being inserted into the ear canal, it is in close contact with the external auditory canal to isolate the sound from entering the middle ear and inner ear, so as to achieve the purpose of sound insulation and protect the hearing of workers. Labor insurance type noise-proof earplugs can prevent eardrum discomfort caused by the sound of the machine. General labor insurance earplugs are equipped with ropes, which are easy to remove at any time. The principle of sleep earplugs is similar to that of anti-noise earplugs. In order to achieve the purpose of daily sleep comfort, they are made of soft and slow-rebound materials, but the anti-noise performance can basically reach or even be better than that of silicone earplugs, so the quality is higher than that of ordinary earplugs. Labor insurance earplugs are better