Hex nuts are to be used with machine bolts to adhere facing materials to prevent tension and shear movement. Specifically in wood to wood, wood to metal, or metal to metal applications. Galvanized zinc grade 2 steel hex nuts are recommended for most general uses and are corrosion resistant. Be sure to pre-drill any holes and to use washers and bolts that are a similar grade and finish.WARNING: This product can expose you to lead which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to