The main application of steel structure bolt nut is in steel structure engineering project to connect the nodes of steel plate thick steel structure. Better fastening characteristics, used for steel structure and engineering projects, a fastening effect. In the general steel structure, the required steel structure bolts are above 8.8 grade, there are also 10.9,12.9. All of are high-toughness steel structure bolts. Sometimes the bolts on the steel structure do not use the electroplating process, but use the primary color can be. Steel structure bolts are divided into torsion-shear high strength bolts and large hexagonal head high strength bolts. Large hexagonal high strength bolt belongs to the high toughness level of general screws, torsional shear high strength bolt is an improved version of large hexagonal high strength bolt, in order to better engineering construction.1. A complete set of our own team to support your selling. We have outstanding R&D team, exquisite technology team and good service sales team to offer our customer the best service and products. We are both manufacturer and trading company. 2. We have our own factories and have formed a professional production system from material supplying and manufacture to sale, as well as a professional R&D team. We always keep ourselves updated with market trends. We are ready to introduce new technology and service to meet the market needs. 3. We have our own brand and attach much significance to quality. The manufacture of products maintains ISO9001 Quality Management. 4. Handan City Tiancong Fastenel ManufacturingCo.,Ltd. is an ISO9001 approved factory, located in Yongniar Weizhuang Industrial Zone, Handan City, Hebei Province, China Fastene Manufacturing Base, with more thar 30 years of professional manufacturinc experience in fastener industry. 5. (Difficult control reason / force majeure not included) 100% in time after-sales guaranteed! Refund or Resent goods can be discussed based on the damaged quantity. 6. 8:30-17:30 within 10 min get response; We will get back to you within 2 hours when not in office; Sleeping time is saving energy. For give you more effective feedback, pls leave message, we will get back to you when wake up!