1. A heart medical thread buckle, medical protective mask, medical protective mask is suitable for medical personnel and related staff to protect from air borne respiratory infectious diseases. It is a kind of close fitting self-priming filtering medical protective equipment with high protection level, especially suitable for patients with respiratory tract infection diseases transmitted by air or near distance through droplets in diagnosis and treatment activities. It can filter the particles in the air and block the droplets, blood, body fluid, secretion droplets, etc. it belongs to disposable products. Medical protective masks can prevent most bacteria, viruses and other pathogens. Who recommends that medical personnel should use protective masks against particles to prevent virus infection in the air of hospitals. Disposable masks belong to class II medical devices. The outer layer of disposable respirator often accumulates a lot of dust, bacteria and other dirt in the outside air, while the inner layer blocks the exhaled bacteria and saliva, so the two sides can not be used alternately. Otherwise, the dirt on the outer layer will be inhaled into the human body when it is directly close to the face and become the source of infection. When the mask is not worn, it should be folded into a clean envelope, and the side close to the mouth and nose should be folded inward. Do not put it into the pocket or hang it around the neck. According to the ability of dust and gas prevention, masks can be divided into three categories. 1. Fashion decorative masks can not block bacteria and viruses. All kinds of fashionable decorative masks have various styles and colorful cartoon patterns. This kind of mask belongs to amateur class. It has no other function except to block dust, prevent paparazzi and keep warm. 2. Gauze mask can only block large dust, such as gauze mask, ordinary disposable mask and disposable medical mask. It is mainly made of ordinary non-woven fabric or several layers of cotton gauze, which meets the relevant registered product standard (yzb). This kind of ordinary mask can only block the larger dust particles or aerosols, but can not effectively prevent bacteria, viruses and other pathogenic microorganisms. 3. Professional masks can prevent most bacteria and viruses. These professional masks include medical surgical masks and medical protective masks (such as N95 masks). It belongs to the management of medical devices and has a unified industry or national production standard. It can prevent most bacteria, viruses and other pathogens. Therefore, it can effectively prevent respiratory infectious diseases such as influenza transmitted by air or close contact with droplets.