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