【Packing List】 We provide you with 20 pieces of M3 stainless steel spring washers, and you can choose washers according to the screw size. 【High-Quality Material】 The lock washer is made of high-quality A2 V2A stainless steel, with a smooth surface, resistant to rust and deformation. The spring washers offer excellent corrosion resistance, suitable for outdoor use and humid environments. They withstand daily stress while ensuring a long service life. 【Practical Features】 All metric lock washers have left-handed spirals. This prevents clockwise loosening due to vibration. The asymmetrical serrated edge bites into unhardened screws and nuts during tightening, providing a firmer hold than wave washers, but only for right-hand thread applications. 【Easy Installation】DIN 127 Type B washers are slotted and spirally curved. They generate a spring force between the fastener head and the base material, pressing the washer firmly against the bracket and the thread against the nut. This increases friction and rotational resistance. 【Wide Applicability】Stainless steel lock washers are used in light industry, chemical industry, metallurgy, construction, shipbuilding, automotive, electrical, and aerospace. They are also used in motorcycles, fences, furniture, renovation, decoration, outdoor installations, and DIY.