1、These hex nuts are made of PA66 eco-friendly nylon which has good acid-base resistance and insulation. 2、Hexagonal shape has 6 sides that gives a good granularity of angles for a tool to approach from. 3、These are many common sizes that you can use for general purpose or projects. 4、These hex nuts will be great replacement for industrial and construction fasteners. 5、Used widely in the home and office appliance, communication equipment, ship assembly and other machinery industry. Features: These hex nuts are made of PA66 eco-friendly nylon which has good acid-base resistance and insulation. Hexagonal shape has 6 sides that gives a good granularity of angles for a tool to approach from. These are many common sizes that you can use for general purpose or projects. These hex nuts will be great replacement for industrial and construction fasteners. Used widely in the home and office appliance, communication equipment, ship assembly and other machinery industry. Specification: Color: Black, White (Optional) Material: PA66 eco-friendly nylon Operating Temperature: -20℃~+120℃ Flammability Standard: 94-V2 Size & Quantity: M2*0.2        20pcs M2.5*0.2     20pcs M3*0.2        20pcs M4*0.3        20pcs M5*0.5        20pcs M6*0.5        20pcs M8*0.8        10pcs M10*0.8      10pcs Weight: 66g / 2.3oz (approx.) Package list: 1 box * Nuts