DIN 433 Small-OD Flat Washers
Small-outer-diameter flat washers per DIN 433 (ISO 7092 counterpart) — the reduced-series washer for tight bolt patterns and confined bearing faces, dimensioned M1 to M36 in the collected series.
Last updated: 2026-11
Specifications
DIN 433 is the small-OD, or reduced-series, metric flat washer: for the same bolt size it carries a noticeably smaller outer diameter than the ISO 7089/DIN 125 normal series — 18 mm instead of 21 mm at M10, 34 mm instead of 44 mm at M24 — with the same nominal hole. That reduced footprint is what earns its place: clustered bolt patterns where full-size washers would overlap edges, confined bearing faces on small housings and channels, and assemblies where the washer must stay clear of adjacent geometry. The collected series runs M1 to M36, with thickness scaling from 0.3 mm at the small end to 5 mm at M36.
| Standard | DIN 433 — small outer diameter flat washers (ISO 7092 counterpart) |
|---|---|
| Series range | M1 to M36 in the collected dimension series (metric reduced series) |
| Worked row (M10) | 10.5 mm hole × 18 mm outer diameter × 1.6 mm thick (vs 21 mm OD in the normal series) |
| Worked row (M24) | 25 mm hole × 39 mm outer diameter × 4 mm thick (vs 44 mm OD in the normal series) |
| Selection rule | Choose where full-size washers would overlap in clustered patterns or foul adjacent geometry |
| Stock range | Collected stock statement: M1.5 to M20 in A2 and marine-grade A4 stainless steel |
| Stainless strength classes | A2/A4 austenitic classes 50 (to M39), 70 (to M20), 80 (to M20) — 500/700/800 N/mm² |
| For nominal thread | Hole d min (= nominal) (mm) | Hole d max (mm) | dc max (mm) | dc min (mm) | h nominal (mm) | h max (mm) | h min (mm) | Weight (kg / 1000 pcs) |
|---|---|---|---|---|---|---|---|---|
| M1 | 1.1 | 1.24 | 2.5 | 2.25 | 0.3 | 0.35 | 0.25 | 0.01 |
| M1.2 | 1.3 | 1.44 | 3 | 2.75 | 0.3 | 0.35 | 0.25 | 0.014 |
| M1.4 | 1.5 | 1.64 | 3 | 2.75 | 0.3 | 0.35 | 0.25 | 0.012 |
| M1.6 | 1.7 | 1.84 | 3.5 | 3.2 | 0.3 | 0.35 | 0.25 | 0.017 |
| M1.8 | 2 | 2.14 | 4 | 3.7 | 0.3 | 0.35 | 0.25 | 0.022 |
| M2 | 2.2 | 2.34 | 4.5 | 4.2 | 0.3 | 0.35 | 0.25 | 0.029 |
| M2.5 | 2.7 | 2.84 | 5 | 4.7 | 0.5 | 0.55 | 0.45 | 0.055 |
| M3 | 3.2 | 3.38 | 6 | 5.7 | 0.5 | 0.55 | 0.45 | 0.079 |
| M3.5 | 3.7 | 3.88 | 7 | 6.64 | 0.5 | 0.55 | 0.45 | 0.109 |
| M4 | 4.3 | 4.48 | 8 | 7.64 | 0.5 | 0.55 | 0.45 | 0.14 |
| M5 | 5.3 | 5.48 | 9 | 8.64 | 1 | 1.1 | 0.9 | 0.326 |
| M6 | 6.4 | 6.62 | 11 | 10.57 | 1.6 | 1.8 | 1.4 | 0.79 |
| M8 | 8.4 | 8.62 | 15 | 14.57 | 1.6 | 1.8 | 1.4 | 1.52 |
| M10 | 10.5 | 10.77 | 18 | 17.57 | 1.6 | 1.8 | 1.4 | 2.11 |
| M12 | 13 | 13.27 | 20 | 19.48 | 2 | 2.2 | 1.8 | 2.85 |
| M14 | 15 | 15.27 | 24 | 23.48 | 2.5 | 2.7 | 2.3 | 5.41 |
| M16 | 17 | 17.27 | 28 | 27.48 | 2.5 | 2.7 | 2.3 | 7.63 |
| M18 | 19 | 19.33 | 30 | 29.48 | 2.5 | 2.7 | 2.3 | 8.31 |
| M20 | 21 | 21.33 | 34 | 33.38 | 3 | 3.3 | 2.7 | 13.2 |
| M24 | 25 | 25.33 | 39 | 38.38 | 4 | 4.3 | 3.7 | 22.1 |
| M30 | 31 | 31.39 | 50 | 49.38 | 4 | 4.3 | 3.7 | 38 |
| M36 | 37 | 37.62 | 58 | 56.8 | 5 | 5.6 | 4.4 | 61.5 |
Materials
- Stainless steel A2
- Stainless steel A4
Ordering & documentation
Documents
Shipments are backed by Mill Test Certificate (MTC), Dimensional Report, Salt Spray Test Report on request, with full batch traceability from raw material to finished product. Quality management follows the owner-confirmed compliance list: ISO 9001:2015, RoHS, REACH. Exact document sets are confirmed on the order.
Quotation
- The fastener family (DIN 433 Small-OD Flat Washers) plus the standard designation from your drawing — DIN / ISO / JIS / ASTM / ANSI, or a drawing for custom parts.
- Size (diameter and length), thread type (metric or inch), property class or grade, and coating or finish.
- Quantity per size and your target delivery date.
- Destination country, and any required documents (for example a mill test certificate) so the quote includes them.
Sample & supply
Minimum order quantity is 10,000 pieces. Stock items run 3–7 days. Quantities or variants outside the standard range are confirmed at quotation.
Storage & shipping
Parts are packed for export and shipped factory-direct to buyers in Europe, Asia, the Americas and the Middle East. Store fasteners dry and protected until installation, and keep coated parts in their packaging until use; specific packing and preservation requirements can be stated on the order and confirmed at quotation.
Frequently asked questions
Why choose a reduced-series DIN 433 washer over the standard ISO 7089 series?
Because the extra diameter of a standard washer only pays when it has room to work. In a clustered bolt pattern, full-size washers can overlap or come edge-to-edge, leaving uneven bearing; on narrow flanges, channel webs and small housings, the normal-series OD can hang past the face it is meant to bear on. The DIN 433 series trims the outer diameter — 18 mm versus 21 mm at M10, 39 mm versus 44 mm at M24 — while keeping the nominal hole, so the joint keeps its bearing area where it fits and gives up nothing but the footprint it cannot use.
What is the MOQ and lead time for this washer type?
The minimum order quantity is 10,000 pieces. Stock items ship in 3–7 days; non-stock items are confirmed at quotation. Common sizes in this washer type are widely stocked; confirm the exact schedule against quantity and size mix at quotation.
What should an RFQ for this washer type state?
State the standard designation and form (for example ISO 7090 chamfered or DIN 7980 high-collar), the nominal bolt or screw size it must fit, material and hardness requirements, finish (plain, zinc-plated, or hot-dip galvanized where the assembly calls for it), required certificates such as a mill test report per EN 10204 3.1, and quantity per size — plus destination country.
Request a Quote
Get factory-direct pricing from the manufacturer.
What to include in your inquiry
- ✓ Standard and property class (e.g. DIN 912, ISO 4762, class 8.8) — or a drawing for custom parts.
- ✓ Sizes, lengths and thread type (metric or inch).
- ✓ Quantity per size and your target delivery date.
- ✓ Destination country, plus any coating or finish requirement.
- ✓ Any documents you need with the shipment (e.g. mill test certificate) so the quote includes them.
- ✓ Your inquiry goes straight to the factory team by email and gets a reply within 24 hours.
- ✓ Factory-direct pricing
- ✓ Standard and custom specifications
- ✓ Factory-direct export to buyers in Europe, Asia, the Americas and the Middle East
- ✓ Full fastener family support