1. These four prongs prevent the Tnut from rotating when inserted and tightened into wood pieces. They are used to provide a strong, reliable, and easytoinstall threaded insert in wood and particle boards. The prongs stop the Tnut from turning when it is inserted into wood pieces and tightened. 2. These Tnuts are an replacement for woodworking and construction fasteners and can also be an essential accessory for furniture assembly projects. 3. Installation First, drill a hole matching the outer diameter of the barrel. Insert the barrel of the pronged Tnut into the hole, then tap the bottom of the nut flange with a hammer to drive the prongs into the wood, creating a stable and secure nut connection. 4. Usage suitable for solid wood products, plywood, and particle boards to create a very strong joint. Commonly used in fixed cabinets, table and chair legs, leather bags, climbing wall installations, etc.