This is a BoltShield® solution to protect stud bolts and nuts where you have limited space or stud bolt larger than 4″ / M100 size.
website:https://www.jhmindustry.com/
Shanghai Jian & Mei Industry and Trade Co., Ltd. is the company which manufacture and export fasteners and metal hardware, founded in 2006, with import-export authority. Now, 80% products export to all over the world and 20% sell in domestic market.