M3 Internal Tooth Lock Washer, 304 Stainless Steel - ILWA2M3

Made in 304 (A2) stainless steel, the Metric Internal Tooth Lock Washer is a washer with teeth around its inner edge. The teeth bite into the fastener and the surface to resist loosening, and the smaller outer diameter is useful where space is tight.

Made from 304 (A2) stainless steel, a standard austenitic grade with good everyday corrosion resistance. It is a sound choice away from the coast; in chloride-exposed settings, step up to 316 (A4). Metric sizes are written M followed by the nominal thread diameter in millimetres, so M10 is a 10 mm thread.

You can choose from 9 variants, covering sizes M3 to M20. Pack quantities depend on size: packs of 50 to 500.

In wet conditions, keep stainless steel apart from aluminium and galvanised steel with a washer or sleeve, to reduce the risk of galvanic corrosion.

Where this product is used

• Electrical and earthing connections
• Indoor architectural and joinery work
• Outdoor structures away from the coast
• Small assemblies and screw heads where outer diameter is limited
• Bulk jobs and trade or maintenance stores buying in larger packs
• Small sizes for enclosures, instruments and light fittings

Features

• A2 (304) stainless steel for indoor, fresh water and general outdoor use
• Teeth around the inner edge bite into the surface
• Resists loosening under vibration
• Metric thread sizes match the nuts, bolts and tapped holes in most Australian-supplied equipment
• Pack quantities to suit trade and bulk buying: packs of 50 to 500
• Choice of 9 sizes, M3 to M20

Key specifications

Selecting the right option

Teeth mark the surface they bite into, so avoid them on finished or painted faces. Internal teeth are usually chosen for screw heads and where the outer diameter must stay small. Near the coast, around pools or in marine settings, use the A4 (316) version instead: Internal Serrated Tooth Lock Washer Stainless Steel.