Application items: filter type self-rescuer, gas detection instrument, dust mask, mining raincoat, mine blaster, application details: joint bolts are widely used: low temperature and high pressure valves, pressure pipelines, fluid engineering, petroleum drilling and production equipment, Oilfield equipment and other fields are often used in disassembly and connection occasions or tools such as the valve industry, folding bicycles, baby carriages. Due to the convenient and fast use of live bolts, the use of supporting bolts plays a role of connection and fastening. Wide and wide.