Upon first look they look slightly complicated, like something from an infomercial that you might as well not even try, just save the money that would surely be lost on purchase. However, expansion bolts can be quite useful, as well as reliable and dependable. Definitely not something you would find in an infomercial. A type of anchor bolt, it is comprised of a bolt, nut and lead sleeve assembly that is able to expand when tightened. While most bolts will have to crack the surface they are placed into, these models instead fill the deformities; not only improving the overall look of the structure, but also firmly strengthening the connection. It is able to create a firm bond and offers an extreme carrying weight. This provides additional advantage in industries that might work in vibratory environments because it helps reduce the risk of crack in the structure. Some industries that make use of expansion bolts include construction, masonry walls, turbines, motor couplings, gears, mining, seating and sign installation.