Product and application brief
Toothed lock washers are thin annular parts with teeth formed at the outer edge or around the clearance opening. They are also described commercially as star or tooth washers. Identify tooth location, body form and exact reference together: the label lock washer does not identify a universal geometry or prove resistance to loosening.
Product forms and reference names
| Product form / field | Reference and distinguishing details |
|---|---|
| External teeth — DIN 6797 A reference | Teeth project outward from the annular body; the clearance opening has a plain circular outline. Bossard identifies its type A toothed-washer entry with the legacy DIN 6797 A reference. |
| Internal teeth — DIN 6797 J reference | Teeth project into the opening while the outside body has a plain circular outline. Bossard identifies its type J entry with DIN 6797 J; check the tooth-tip opening rather than substituting by outer diameter. |
| Serrated washers — DIN 6798 reference | DIN Media lists DIN 6798 separately as serrated lock washers. Do not treat toothed and serrated trade names as proof of identical geometry; confirm the selected pattern, form and drawing. |
| Special body or tooth patterns | Non-flat bodies or other tooth layouts need their own selected specification or drawing. The generic illustration depicts internal and external tooth locations, not every standard form or exact tooth count. |
Recognize the tooth location
Compare the inner opening and outer edge, not only the star-like silhouette. External teeth need a defined outside envelope; internal teeth change the opening profile. Include the mating fastener and bearing-face geometry where they control selection. Neither type is a split helical washer or a paired wedge-locking system.
Separate reference number, form and edition
DIN Media marks DIN 6797:1988-07 and DIN 6798:1988-07 as withdrawn. Supplier catalogue references remain useful identifiers for legacy parts but are not current-standard status or evidence that our products conform. Keep A/J form letters with the reference; do not infer a current ISO equivalent or substitute DIN 6798 for DIN 6797 solely from a trade name.
Section thickness and formed height
Record the required nominal fastener size, opening/clearance definition, outside envelope and sheet thickness. A tooth twisted out of the body plane can make overall free height different from sheet thickness. Tooth count, profile and formed height follow the selected specification or drawing, not the generic image. Material and surface finish are separate fields.
Application claims need separate evidence
A toothed appearance does not establish an electrical bonding rating, vibration-locking guarantee or approved replacement for another locking system. Identify the assembly requirements and required inspection documents separately. This page supplies product-identification information, not tightening torque, load capacity or a reuse recommendation.
Specification fields
| Product form / field | Reference and distinguishing details |
|---|---|
| Identity | Internal or external teeth; exact reference, form letter and edition, or controlled drawing/revision. |
| Size and mating geometry | Nominal fastener size, opening/clearance definition, outside envelope and available bearing-face dimensions. |
| Tooth and body shape | Tooth location, profile/count where specified, body form and formed overall height. |
| Thickness and material | Sheet thickness, tolerances, material designation and any specified hardness/inspection requirements. |
| Surface condition | Finish or coating specification; application-specific surface and document requirements, not inferred from silver appearance. |
| Quantity and attachments | Quantity with units, size-by-size list and drawing/specification; list unresolved details separately. |
Common product questions
How do internal and external tooth washers differ?
External teeth are formed around the outside edge; internal teeth extend into the clearance opening. Match the tooth location, opening and outside envelope to the selected specification instead of ordering by nominal fastener size alone.
Are DIN 6797 and DIN 6798 interchangeable names?
No automatic equivalence is established here. DIN Media identifies toothed washers and serrated washers separately; both 1988-07 editions are withdrawn. Confirm the number, form, edition and geometry required by the actual bill of materials.
Does a tooth washer guarantee locking or electrical bonding?
No. The name and illustration are not performance evidence. Assembly-specific locking or bonding requirements require their own verification; no capacity, torque, reuse or approval is promised by this page.
Related washer types
Product references
References checked 6 October 2026 explain product identity. Third-party model names and approvals are not FastenerBridge brand affiliation, stock or certification claims. Final geometry and requirements follow the selected specification.
Related specification guides
- Read standard numbers, editions and proposed alternatives
- Identify assembly inputs and product-specific installation instructions
- Explore related connection arrangements
These guides explain specification choices; they are not an approval, substitution rule or installation value for this product.