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Zoro Select

Zoro Select M37480.180.0001 Internal Tooth Lock Washer M18 50 pcs

SKU CH-08R3-0863P

Internal-tooth lock washers, M18, zinc-plated spring steel, DIN 6798 J, pack of 50

  • TypeWashers
  • SizeM18
  • Serrated internal teeth bite into M18 fasteners preventing loosening
  • Spring steel hardened to 350-425 HV10 resists permanent deformation
  • Zinc-plated finish protects against corrosion in general-purpose use
  • Meets DIN 6798 J standard ensuring reliable dimensional quality
  • Pack of 50 washers covers multiple assembly or maintenance jobs

Internal Tooth Lock Washer M18

Zoro Select M37480.180.0001 internal tooth lock washers are spring steel fasteners with zinc plating for corrosion resistance. Each washer fits M18 bolts with a 19.0 mm inside diameter and 30.0 mm outside diameter. The 1.40 mm thickness provides spring action to maintain bolt tension. A pack contains 50 pieces for production or maintenance use.

Suited for general purpose assembly and repair

These washers suit mechanics and assemblers securing M18 fasteners in machinery, vehicles or structural joints where vibration loosening is a concern. They meet DIN 6798 J specifications for serrated internal tooth lock washers. Buyers needing different bolt sizes, external tooth patterns or non-metallic locking methods should look at other hardware options.

Spring steel retains clamping force under vibration

The 350-425 HV10 hardness gives the serrated teeth a firm bite into the bolt head and mating surface. This resists rotational loosening during sustained vibration better than a plain flat washer. Zinc plating protects the spring steel from rust so the locking performance remains consistent over the service life of the joint.

Highlights

  • Serrated internal teeth bite into M18 fasteners preventing loosening
  • Spring steel hardened to 350-425 HV10 resists permanent deformation
  • Zinc-plated finish protects against corrosion in general-purpose use
  • Meets DIN 6798 J standard ensuring reliable dimensional quality
  • Pack of 50 washers covers multiple assembly or maintenance jobs

Specifications

BrandZORO SELECT
TypeWashers
SizeM18

Questions about this item

What bolt diameter must I already have for these M18 internal-tooth lock washers to fit?

They are made for M18 bolts, with a 19.0 mm inside diameter that matches the standard shank size.

Will the 1.40 mm thickness and 30.0 mm outside diameter let me stack them with existing flat washers on the same M18 bolt?

Yes, the 1.40 mm thickness adds minimal height while the 30.0 mm outside diameter covers standard M18 flat-washer footprints.

After torquing the assembly, how can I confirm the serrated teeth are gripping properly?

Inspect the joint for visible tooth impressions on both the bolt head and the mating surface, and verify no rotational movement occurs under vibration.

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