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Nuts · DIN 557

A2 Stainless Steel Square Nuts

For Square Nuts in A2 Stainless Steel, the controlling decisions are corrosion, strength and service temperature. This guide summarizes those three for A2 Stainless Steel Square Nuts and lists every size we supply.

Why Choose A2 Stainless Steel for Square Nuts

The most common stainless grade for indoor and general outdoor fasteners. For square nuts, this matters when good general corrosion resistance is the primary requirement.

Mechanical & Physical Properties

Grade designationA2-70 (304)
Magnetic responseLargely non-magnetic
Service temperatureapprox. -200 °C to +400 °C
Corrosion characteristicGood general corrosion resistance

Galvanic & Galling Considerations

Two important notes for stainless square nuts: (1) stainless can gall on stainless threads under load — use a thread lubricant or anti-galling compound, especially for M6 and below; (2) when joined to aluminum or galvanized steel, stainless can drive galvanic corrosion of the less-noble metal in wet service — isolate with a coating or sleeve where appropriate.

Comparable Grades

For Square Nuts, the alternative stainless grade is A4 (316). A2 (304) suits general indoor and outdoor service; A4 (316) adds molybdenum for marine and chloride environments. Where higher strength matters more than corrosion, switch to plated alloy-steel class 8.8 or 10.9.

Sizes of Square Nuts Available in A2 Stainless Steel

SizePitch (mm)Width across flats s (mm)Width across corners e min (mm)Nut height m (mm)Reference standardNotes
M50.88.011.14.0DIN 557 / DIN 562Square nut, general / channel use
M61.010.013.95.0DIN 557 / DIN 562Square nut, general / channel use
M81.2513.018.06.5DIN 557 / DIN 562Square nut, general / channel use
M101.517.023.68.0DIN 557 / DIN 562Square nut, general / channel use
M121.7519.026.510.0DIN 557 / DIN 562Square nut, general / channel use
M162.024.033.513.0DIN 557 / DIN 562Square nut, general / channel use
M202.530.042.016.0DIN 557 / DIN 562Square nut, general / channel use

Technical Drawing

Customize the parameters below — every spec field is editable, and the drawing redraws to match the values you choose. Changing the size will snap the other fields to that size's standard values; you can then override any individual value.

Sends the selected values to the quote form below.

Request a Quote

Adjust the parameters in the drawing above and click "Request this configuration" to send the exact specification straight to this form.

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Specification
Business Information

Dimensions & Specifications (DIN 557)

SizePitch (mm)Width across flats s (mm)Width across corners e min (mm)Nut height m (mm)Reference standardNotes
M50.88.011.14.0DIN 557 / DIN 562Square nut, general / channel use
M61.010.013.95.0DIN 557 / DIN 562Square nut, general / channel use
M81.2513.018.06.5DIN 557 / DIN 562Square nut, general / channel use
M101.517.023.68.0DIN 557 / DIN 562Square nut, general / channel use
M121.7519.026.510.0DIN 557 / DIN 562Square nut, general / channel use
M162.024.033.513.0DIN 557 / DIN 562Square nut, general / channel use
M202.530.042.016.0DIN 557 / DIN 562Square nut, general / channel use

Frequently Asked Questions

Should I choose A2 Stainless Steel or A4 (316) for Square Nuts?

For Square Nuts, A2 Stainless Steel suits general indoor and outdoor use; A4 (316) is preferred for marine, coastal and chemical environments. Choose by corrosion exposure first.

Can A2 Stainless Steel Square Nuts gall during installation?

Yes — stainless on stainless is prone to thread galling under load, especially at smaller sizes. Use an anti-galling lubricant or wax thread compound, and slow the tightening rate where possible.

Is A2 Stainless Steel food-grade?

A2 (304) is widely accepted for food contact in non-chloride environments; A4 (316) is preferred where chlorides are present.

Can A2 Stainless Steel Square Nuts be used with aluminum?

Yes, but stainless drives mild galvanic corrosion of aluminum in wet service — isolate with a coating, sleeve or paint, or accept the trade-off if the joint is dry and indoor.

How do I request a quotation?

Use the technical drawing on this page to pick the exact configuration, then submit it with the quote form. We respond within one business day.