Quality Material: Threaded Nuts made of carbon steel, zinc alloy, high hardness, corrosion resistance, good fixing effect. Size Includes: These Threaded Nuts contains an assortment of rivets 40pcs M4 x 8, 40pcs M4 x 10, 30pcs M5 x 10, 15pcs M6 x 10, 20pcs M6 x 15, 20pcs M8 x 20, which could meet your different needs. Application: This hex nut screw is suitable for various woods, especially in the combination of furniture, stable and durable connection. Thread design: Hexagon socket nut of external and internal thread, good tensile strength, can effectively prevent and remove due to torsion or vibration. Easy to install: just drill the appropriate size hole (2mm larger hole than the nut) and install it hexagonal insert nuts with a hex wrench (PLEASE DO NOT OVER TIGHTEN), the tapered outer threads make it hard to fall off is vibrations.