Butterfly Shape Spring Lock Washers Single Face Serrate Metric Fasteners Assortment M3 M4 M5 M6 M8 M10 M12 M14 M16 M18 M20 Anti-Loosening Washers for Mechanical Assembly (20,M20)

These butterfly shape spring lock washers with single face serrated edges are manufactured from A2 stainless steel for dependable fastening solutions. Designed to prevent loosening caused by vibration, they are widely applied in mechanical equipment, automotive repair, furniture assembly, and household maintenance. The metric assortment includes M3, M4, M5, M6, M8, M10, M12, M14, M16, M18, and M20 sizes to meet diverse installation requirements. The serrated surface improves locking force, while the spring structure ensures sustained clamping pressure. Ideal for professionals and DIY users seeking secure and stable threaded connections.

• Made of A2 stainless steel, these butterfly spring lock washers feature single-face serrated design to deliver reliable anti-loosening performance under vibration and dynamic loads.
• Metric sizes range from M3 to M20, covering most household, automotive, machinery, and furniture fastening needs for versatile project use.
• Serrated contact surface enhances grip between fasteners and mating surfaces, reducing rotation and maintaining tight connections in long-term use.
• Butterfly spring structure provides consistent elastic tension, suitable for bolts, nuts, and threaded fasteners in industrial and daily assembly.
• Corrosion resistant and stable in various environments, easy to store and select with complete sizing for repair, construction, and equipment maintenance.