Lag bolts, also known as lag screws, are heavy-duty fasteners used primarily in woodworking and construction. They have a thick, coarse thread that provides a strong grip in wood and other materials. Typically made of steel, lag bolts are designed to be driven into pre-drilled holes, allowing for secure connections between large pieces of wood or metal. These fasteners come in various lengths and diameters, making them versatile for different applications. Commonly used in building decks, securing beams, and attaching heavy fixtures, lag bolts are essential for ensuring structural integrity in many projects. Proper installation requires a wrench or socket for tightening.