DIN 661 Countersunk Solid Rivets
Flat countersunk head solid rivets per DIN 661 (ISO 1051A equivalent) — M2.5 to M6, lengths to 40 mm, the flush-finished member of the solid rivet line. Steel or A2/A4 stainless; two-sided setting like DIN 660 but with the head seated below the surface.
Last updated: 2026-11
Specifications
DIN 661 is the DIN 660 solid rivet with the head swapped: a flat countersunk head that seats into a matching countersink and finishes flush with the outer sheet. The joint mechanics are the same solid-rivet contract — pre-drilled aligned holes, both-side access, the protruding shank deformed into the closing head — with the collected trade data running M2.5 through M6 at lengths to 40 mm in steel and A2 stainless. The flush head is not cosmetic only: it removes a protrusion that would interfere with sliding mating parts, packing surfaces, airflow or secondary paint, which is why countersunk solid rivets appear on wear strips, guide rails and assembled housings where the rivet line must sit proud-free. Where head height is no obstacle, the round-head DIN 660 keeps the hole prep simpler — no countersink to cut.
| Standard | DIN 661 — flat countersunk head solid rivets; the collected source names ISO 1051A as the equivalent designation |
|---|---|
| Head / body | Flat countersunk head (seats flush in a countersunk hole) with plain cylindrical shank; closing head formed on the tail after insertion |
| Size range | Diameters M2.5–M6; lengths up to 40 mm (collected stock scope) |
| Installation | Two-sided access required; hole countersunk for the head — flush finish on the factory-head side |
| Stainless strength (ISO 3506) | A2/A4 austenitic: property class 50 = 500 N/mm² (to M39), class 70 = 700 N/mm² (to M20), class 80 = 800 N/mm² (to M20) — same base-metal table the source carries for the solid rivet line |
| Stainless chemistry (A2/A4) | A2 (304 family) C ≤0.07, Cr 17.5–19.5, Ni 8.0–10.5; A4 (316 family) adds Mo 2.0–2.5 — per the collected composition table |
| Steel classes | Collected table carries property classes 4.6–12.9 with tempering-temperature minima (425 °C for 8.8–10.9, 380 °C for 12.9) |
| MOQ / lead time | 10,000–50,000 pieces by size; 10–20 days |
Materials
- Steel (property classes 4.6–12.9)
- Stainless steel A2 (304 family)
- Stainless steel A4 (316 family)
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 661 Countersunk Solid Rivets) 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 10,000–50,000 pieces depending on size. Standard production run 10–20 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
DIN 660 round head or DIN 661 countersunk — how do I choose between the two solid rivets?
By the outer surface, not the joint strength — the shank carries the load identically once set. The DIN 660 round head sits on top of the sheet and needs only a plain hole, which keeps preparation cheap and adds head bearing on soft material. The DIN 661 countersunk head needs a countersink but finishes flush — the answer when the rivet line must not catch sliding parts, stand proud of a packing face, or disturb airflow and paint. Both set the same way: both-side access, deformation of the plain end into the closing head.
What is the MOQ and lead time for these rivets?
Minimum order quantity is 10,000–50,000 pieces depending on size and material. Standard production lead time is 10–20 days. Common blind rivet sizes are widely stocked — confirm the exact schedule against quantity and size mix at quotation.
What should an RFQ for these rivets state?
State the rivet subtype (open-end, closed-end, structural blind rivet or rivet nut), body diameter, grip range or total material thickness, head style (dome, countersunk or large flange), body and mandrel materials (for example aluminum body with steel mandrel, or all-stainless), finish, 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