M3 Spring Lock Washers DIN 127B – Rectangular Section, Bright Zinc Plated

Rectangular-section spring lock washers engineered to DIN 127B, providing secure vibration-resistant fastening across metric sizes M3–M22.

Key Benefits & Features

• Manufactured to DIN 127B specifications for consistent dimensions and performance.
• Rectangular-section coil delivers firm locking action to resist loosening under vibration or dynamic loads.
• High-grade spring steel hardened to 140 HV offers resilience and long service life.
• Bright zinc plated (BZP) for corrosion resistance and a clean, professional finish.
• Wide size range from M3 to M22; inner diameters 3.1–18.2 mm with matching outer diameters 6.2–29.4 mm.
• Suitable for automotive, engineering, construction and DIY applications where secure fastening is critical.
• Easy to install; helps prevent leakage, isolates joints and resists pressure dispersion.

Use Cases

• Preventing bolt or nut loosening in machinery, engines and vibrating assemblies
• Securing structural joints in construction and civil engineering
• Automotive repairs, especially on components subject to vibration
• Equipment maintenance and general engineering projects
• DIY workshop tasks requiring reliable locking washers

Variants (Inner Ø × Outer Ø × Thickness)

• M3: 3.1 mm × 6.2 mm × 0.8 mm (≈0.12" × 0.24" × 0.03")
• M4: 4.1 mm × 7.6 mm × 1 mm (≈0.16" × 0.30" × 0.04")
• M5: 5.3 mm × 7.8 mm × 1.5 mm (≈0.21" × 0.31" × 0.06")
• M6: 6.1 mm × 11.8 mm × 1.4 mm (≈0.24" × 0.46" × 0.06")
• M8: 8.1 mm × 14.8 mm × 2 mm (≈0.32" × 0.58" × 0.08")
• M10: 10.2 mm × 18.1 mm × 2.5 mm (≈0.40" × 0.71" × 0.10")
• M12: 12.2 mm × 20.1 mm × 3 mm (≈0.48" × 0.79" × 0.12")
• M14: 14.2 mm × 24.1 mm × 3.2 mm (≈0.56" × 0.95" × 0.13")
• M16: 16.2 mm × 27.4 mm × 3.5 mm (≈0.64" × 1.08" × 0.14")
• M18: 18.2 mm × 29.4 mm × 3.5 mm (≈0.72" × 1.16" × 0.14")

Compatibility / Fittings

• Fits standard metric bolts and screws of the same nominal diameter (M3–M22).
• Suitable for use with nuts and threaded inserts; ensure matching grade and finish for best performance.
• Compatible with flat washers (Form A/B/C) when additional load distribution is required.

Installation & Tips

• Select the washer size that matches the bolt’s nominal diameter (e.g. M8 washer for an M8 bolt).
• Place the washer between the bolt head or nut and the material to be secured; ensure correct orientation for rectangular-section coils.
• For high-vibration applications, combine with appropriate thread-locking nuts or adhesives.
• Do not exceed recommended torque values for the bolt to avoid damaging the washer.
• Use with matching bright zinc plated bolts and nuts to maintain corrosion resistance.