Made of nylon, good toughness, anti-corrosion, anti-aging, suitable for indoor, outdoor or humid environments. Suitable for door handles, machinery industry, and other small repairs around the shop, garage or home furniture fastener, etc. Specification:Material: NylonStandard: MetricThread Type: CoarseThread Diameter: M4Thread Pitch: 0.7mmScrew Size:20mm x 22.6mm/0.79inch x 0.89inch;(Total Height x Screw Length)Hex Nut Size: 6.7mm x 3.8mm/0.26inch x 0.15inch;(Hex Width x Height)Package Content: 50 x Screws Hex Nut Flat Washer Assortment Kit