Stainless Steel External Tooth Lock Washers - Grade 202, 304, 316, A2, A2-70

External Tooth Lock Washers are a type of lock washer featuring multiple outward-facing teeth (serrations) around the outer edge. These teeth bite into the surface of the mating materials to resist rotation and prevent loosening caused by vibration or torque. They are ideal for applications requiring a strong grip on larger bearing surfaces.

Spring Lock Washer Sizes and Dimensions

Below is a standard technical specification table for External Tooth Lock Washers (based on common metric sizes as per DIN 6798-A or ANSI B18.21.1)

Washer Size (Nominal Bolt Size)	Inner Diameter (d)	Outer Diameter (D)	Thickness	Number of Teeth	Standard
M2	2.2 mm	4.8 mm	0.3 mm	8–10	DIN 6798-A
M3	3.2 mm	6.2 mm	0.4 mm	10–12	DIN 6798-A
M4	4.3 mm	7.6 mm	0.5 mm	10–12	DIN 6798-A
M5	5.3 mm	9.2 mm	0.6 mm	12–14	DIN 6798-A
M6	6.4 mm	11.0 mm	0.8 mm	12–14	DIN 6798-A
M8	8.4 mm	14.5 mm	1.0 mm	14–16	DIN 6798-A
M10	10.5 mm	18.0 mm	1.2 mm	16–18	DIN 6798-A
M12	13.0 mm	21.0 mm	1.4 mm	16–18	DIN 6798-A
M16	17.0 mm	27.0 mm	1.6 mm	18–20	DIN 6798-A
M20	21.0 mm	33.0 mm	2.0 mm	20–22	DIN 6798-A

Toothed Design: Teeth on the outer diameter improve grip and locking strength.
Locking Function: Prevents nuts, bolts, and screws from loosening under vibration.
Surface Penetration: Teeth bite into both mating surfaces to secure the fastener.
Ideal for: Large head screws or bolts where internal clearance isn't an issue.
Carbon Steel (Zinc Plated / Black Oxide)
Stainless Steel (SS304 / SS316)
Phosphor Bronze (for electrical conductivity)

Key Features

External Tooth Lock Washer Specifications, Sizes And Schedules

Specifications	Details
Sizes And Schedules	M3 to M100
Minimum Order Quantity	100 Unit
Packaging Type	ROLL
Bimetallic Material	Aluminium and Copper
Shape	Round
Surface Finish	Metal Coated
Standard	AISI, ASTM, DIN, GB
Material	Aluminium
Thickness	2-8mm

Material Comparison for External Tooth Lock Washers

Material	Grade	Corrosion Resistance	Strength	Magnetic	Common Finish	Applications
Carbon Steel	Low/Medium Carbon	Low	High	Yes	Zinc Plated / Black Oxide	General purpose, dry environments
Stainless Steel	SS304	High	Medium	Slight	Natural / Polished	Automotive, marine, corrosive environments
Stainless Steel	SS316	Very High	Medium	No	Natural / Polished	Marine, chemical, high-corrosion exposure
Phosphor Bronze	C51000, C54400	Moderate to High	Medium	No	Natural / Tinned	Electrical, marine, non-magnetic settings
Beryllium Copper	Alloy 25	High	High	No	Natural	Aerospace, electronics, high fatigue loads
Spring Steel	EN42J, SAE 1070	Low to Moderate	Very High	Yes	Zinc / Dacromet Coating	High-tension applications

Also referred to as star washers, external tooth lock washers feature teeth along the outer edge that grip the bearing surface and prevent fasteners from loosening. They are frequently utilized in scenarios involving vibration or movement to ensure a strong and reliable connection.

Material

Stainless Steel (304/316)

Thickness

2-8mm

Inner Diameter

2.2 mm - 21.0 mm

Outer Diameter

4.8 mm - 33.0 mm

Secure Fastening

As the teeth sink into the material, friction and resistance are generated to prevent loosening.

Vibration Resistance

Their effectiveness is especially notable in settings where vibrations may lead to loosening of fasteners.

Strong Locking Efficiency

External teeth have a more secure grip than internal tooth lock washers, thanks to their larger radius and enhanced torsion resistance.

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