HIGH QUALITY: These insert nuts are made of high-quality zinc-plated carbon steel material which provides strength and offers good corrosion resistance in many environments. EASY TO USE: They are versatile threaded insert nuts that you can easily drive with them, easy to use. FEATURES: Insert nuts are advantageous over barrel nuts and T-nuts because they can be installed from one side of the workpiece. ASSORTED SET: There are 6 different sizes of nuts (see the detail size in the description or pictures) so you can handle your project freely. NOTE: The pre-drilled hole should be as deep as the length of the insert nut plus any portion of the bolt that may be screwed past the end of the nut into the workpiece. Description: An insert nut provides a threaded socket for a wooden workpiece, similar to a wall anchor. These insert nuts are inserted into a pre-drilled hole with a screw, in this case, the external protrusions bite into the wood, preventing the nut from turning or coming out. Features: These insert nuts are made of high-quality zinc-plated carbon steel for durability and rust protection. The screw-in nuts have an external thread and a hex socket drive. They are screwed in with a hex key. Insert nuts are advantageous over barrel nuts and T-nuts because they can be installed from one side of the workpiece. There are screw-in nuts in different sizes and different screw sizes that you can choose for your project. The pre-drilled hole should be as deep as the length of the insert nut plus any portion of the bolt that may be screwed into the workpiece beyond the end of the nut.