--- title: "Stainless Steel DIN7991 SS304 M3 – M56 Half Thread Hexagon Socket Countersunk Head Machine Screw" description: "Stainless Steel DIN7991 SS304 M3 – M56 Half Thread Hexagon Socket Countersunk Head… — Countersunk & Flat-Head Machine Screws." url: https://engineeringhardware.com/product/stainless-steel-din7991-ss304-m3-m56-half-thread-hexagon-socket-countersunk-head/ source: Engineering Hardware & Fasteners --- # Stainless Steel DIN7991 SS304 M3 – M56 Half Thread Hexagon Socket Countersunk Head Machine Screw [![Stainless Steel DIN7991 SS304 M3 – M56 Half Thread Hexagon Socket Countersunk Head Machine Screw](https://img.engineeringhardware.com/Stainless-Steel-DIN7991-SS304-M3-M56-Half-Thread-Hexagon-Socket-Countersunk-Head-Machine-Screw.webp)](https://img.engineeringhardware.com/Stainless-Steel-DIN7991-SS304-M3-M56-Half-Thread-Hexagon-Socket-Countersunk-Head-Machine-Screw.webp) - Standard & made-to-drawing parts - Checked before shipping - Air, sea & express delivery [Screws › Countersunk & Flat-Head Machine Screws](https://engineeringhardware.com/fastener-products/screws/countersunk-flat-head-machine-screws/) Updated 2026-11-04 · [Markdown version](https://engineeringhardware.com/product/stainless-steel-din7991-ss304-m3-m56-half-thread-hexagon-socket-countersunk-head.md) US$0.024 / piece MOQ 10,000 pieces · Final price confirmed in your quote - **Head Style:** Counter Sunk Bolt - **Standard:** DIN, GB, ANSI, BSW, JIS, GOST - **Grade:** A2-70 - **Customized:** Support (Size/Grade/Surface/Head/Driver etc.) - **Package Size:** 26.00cm * 26.00cm * 10.00cm - **Material:** Stainless Steel Get a quote [WhatsApp](https://wa.me/8615999653684?text=Hi%20Engineering%20Hardware%20%26amp%3B%20Fasteners%2C%20I%20would%20like%20a%20quote%20for%3A%20Stainless%20Steel%20DIN7991%20SS304%20M3%20%26%238211%3B%20M56%20Half%20Thread%20Hexagon%20Socket%20Countersunk%20Head%20Machine%20Screw%20%E2%80%94%20https%3A%2F%2Fengineeringhardware.com%2Fproduct%2Fstainless-steel-din7991-ss304-m3-m56-half-thread-hexagon-socket-countersunk-head%2F) Specifications are as listed for this product. Engineering Hardware & Fasteners confirms ratings, mating parts, compatibility, packing and lead time with you before you order. ## Specifications | Groove | Socket | | --- | --- | | Connection | Common Bolt | | Head Style | Counter Sunk Bolt | | Standard | DIN, GB, ANSI, BSW, JIS, GOST | | Grade | A2-70 | | Service | Customized | | Customized | Support (Size/Grade/Surface/Head/Driver etc.) | | OEM ODM | Support | | Transport Package | 26 * 26 * 10 Cartons in Bulk | | Specification | M6X100 or Customized | | Origin | Made in China | | HS Code | 7315189001 | | Production Capacity | 220mpieces/Year | | Package Size | 26.00cm * 26.00cm * 10.00cm | | Package Gross Weight | 21.000kg | | Customization | Available | | Material | Stainless Steel | | Type | Countersunk Head | | Shipping Cost | Contact the supplier about freight and estimated delivery time. | | Carton Box | Put into small boxes, then into the carton. The size of the small box can be customized. | | Category | [Countersunk & Flat-Head Machine Screws](https://engineeringhardware.com/fastener-products/screws/countersunk-flat-head-machine-screws/) | ## Technical parameters | Product name | Flat Countersunk head Hex Socket Allen Key Pointed Tail Machine Screw | | --- | --- | | Material | Stainless Steel, etc. | | Specifications | M6 X 100 or Customized | | Surface Treatment | Plain, Polished | | Technology | Cold forging, Hot forming, Machining, Heat treatment, Staming, etc | | Grade | A2-50, A2-70 | | Executive Standard | DIN, ANSI/ASTM, IFI, BS, GB, ISO, JIS, BA, etc. / Customized | | Package | Carton bulk, Carton box, Pallet, etc. | | Estimated delivery time | Negotiation required | | logistics mode | Cusomized | | LOGO customization | support | | Outer packaging customization | support | | Screw Thread | M3 | M4 | M5 | M6 | M8 | M10 | M12 | (M14) | M16 | M20 | | | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | d | | | | | | | | | | | | | | P | Pitch | | 0.5 | 0.7 | 0.8 | 1 | 1.25 | 1.5 | 1.75 | 2 | 2 | 2.5 | | b | ref. | | 18 | 20 | 22 | 24 | 28 | 32 | 36 | 40 | 44 | 52 | | dk | theor. | max | 6.72 | 8.96 | 11.2 | 13.44 | 17.92 | 22.4 | 26.88 | 30.8 | 33.6 | 40.32 | | actual | min | 5.54 | 7.53 | 9.43 | 11.34 | 15.24 | 19.22 | 23.12 | 26.52 | 29.01 | 36.05 | | | ds | max | | 3 | 4 | 5 | 6 | 8 | 10 | 12 | 14 | 16 | 20 | | min | | 2.86 | 3.82 | 4.82 | 5.82 | 7.78 | 9.78 | 11.73 | 13.73 | 15.73 | 19.67 | | | e | min | | 2.3 | 2.87 | 3.44 | 4.58 | 5.72 | 6.86 | 9.15 | 11.43 | 11.43 | 13.72 | | k | max | | 1.86 | 2.48 | 3.1 | 3.72 | 4.96 | 6.2 | 7.44 | 8.4 | 8.8 | 10.16 | | s | Nominal Size | | 2 | 2.5 | 3 | 4 | 5 | 6 | 8 | 10 | 10 | 12 | | max | 12.9 | 2.045 | 2.56 | 3.071 | 4.084 | 5.084 | 6.095 | 8.115 | 10.115 | 10.115 | 12.142 | | | Other property class | 2.06 | 2.58 | 3.08 | 4.095 | 5.14 | 6.14 | 8.175 | 10.175 | 10.175 | 12.212 | | | | min | | 2.02 | 2.52 | 3.02 | 4.02 | 5.02 | 6.02 | 8.025 | 10.025 | 10.025 | 12.032 | | | t | min | | 1.1 | 1.5 | 1.9 | 2.2 | 3 | 3.6 | 4.3 | 4.5 | 4.8 | 5.6 | | Minimum tensile load(N)-8.8 | | 3220 | 5620 | 9080 | 12900 | 23400 | 37100 | 53900 | 73600 | 100000 | 162000 | | | Minimum tensile load(N)-10.9 | | 4180 | 7300 | 11800 | 16700 | 30500 | 48200 | 70200 | 96000 | 130000 | 204000 | | | Minimum tensile load(N)-12.9 | | 4910 | 8560 | 13800 | 19600 | 35700 | 56600 | 82400 | 112000 | 154000 | 239000 | | | ,emin=1.14smin | | | | | | | | | | | | | | ,80% of the values specified in ISO 898-1 | | | | | | | | | | | | | ## Description Stainless Steel DIN7991 SS304 M3 – M56 Half Thread Hexagon Socket Countersunk Head Machine Screw is part of our countersunk & flat-head machine screws range (Screws). ### Key details - **Type:** Countersunk Head - **Standard:** DIN, GB, ANSI, BSW, JIS, GOST - **Material:** Stainless Steel - **Grade:** A2-70 - **Head Style:** Counter Sunk Bolt - **Groove:** Socket - **Connection:** Common Bolt - **Service:** Customized Available configurations include head style, standard, grade, customized and package size. Custom sizes, threads, materials, grades, platings and packaging can be quoted on request. ### Ordering through Engineering Hardware & Fasteners Minimum order is 10,000 pieces at US$0.024 per piece. Send one inquiry with the part number, quantity and destination, and Engineering Hardware & Fasteners confirms size, thread, material, grade, finish, price, lead time and shipping, checks the goods before dispatch and ships them to you. ## Frequently asked questions ### What is the minimum order quantity (MOQ) for Stainless Steel DIN7991 SS304 M3 – M56 Half Thread Hexagon Socket Countersunk Head Machine Screw? The listed minimum order is 10,000 pieces, at US$0.024 per piece. Smaller trial quantities or samples can be requested in your inquiry; Engineering Hardware & Fasteners confirms what is possible for your size. ### What are the main specifications of Stainless Steel DIN7991 SS304 M3 – M56 Half Thread Hexagon Socket Countersunk Head Machine Screw? Type: Countersunk Head; Standard: DIN, GB, ANSI, BSW, JIS, GOST; Material: Stainless Steel; Grade: A2-70; Head Style: Counter Sunk Bolt; Groove: Socket. The full specification table and any technical parameter tables are listed on this page. ### Can this product be customized (OEM)? Listed configurations include head style, standard, grade, customized and package size. Size, thread, length, material and grade, surface finish, head marking, packaging and labels can be quoted to your specification or drawing. ### What is the lead time and how is it shipped? Lead time depends on quantity and customization and is confirmed in your quote. Engineering Hardware & Fasteners checks the goods before dispatch and ships by express, air or sea; mixed orders can be consolidated in one shipment. ### Which other countersunk & flat-head machine screws are available? The Countersunk & Flat-Head Machine Screws category lists 2,424 products in different sizes, materials and finishes: [https://engineeringhardware.com/fastener-products/screws/countersunk-flat-head-machine-screws/](https://engineeringhardware.com/fastener-products/screws/countersunk-flat-head-machine-screws/) How we work ## Specified, checked and shipped by Engineering Hardware & Fasteners Engineering Hardware & Fasteners supplies bolts, screws, nuts, washers, anchors, rivets and fastening hardware to equipment makers, contractors, distributors and maintenance teams. Orders go through one controlled process: size, thread, material, grade and finish confirmed, samples approved, dimensions, thread fit and plating checked before packing, then packed for export — standard or made to drawing. - DIN, ISO, ASTM, ANSI, JIS and GB standard parts - Non-standard parts made to your drawing - Dimensions, thread gauges and plating checked before packing - Export cartons and pallets, consolidated mixed orders - Samples available for approval before mass production [![Production floor](https://engineeringhardware.com/wp-content/uploads/2026/11/factory-01-production-floor-1024x683.webp)](https://engineeringhardware.com/wp-content/uploads/2026/11/factory-01-production-floor.webp) Production floor [![Inspection bench](https://engineeringhardware.com/wp-content/uploads/2026/11/factory-02-inspection-bench-768x512.webp)](https://engineeringhardware.com/wp-content/uploads/2026/11/factory-02-inspection-bench.webp) Inspection bench [![Sorting & 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custom quote →](https://engineeringhardware.com/contact/) ## Request a quote for this product ## Related products [All Countersunk & Flat-Head Machine Screws →](https://engineeringhardware.com/fastener-products/screws/countersunk-flat-head-machine-screws/) [![ISO7046 Zinc-Nickel Alloy Phillips Head Countersunk Screws with Flat Head Machine Screws for Solar Energy Special High Salt Spray](https://img.engineeringhardware.com/ISO7046-Zinc-Nickel-Alloy-Phillips-Head-Countersunk-Screws-with-Flat-Head-Machine-Screws-for-Solar-Energy-Special-High-Salt-Spray.webp)](https://engineeringhardware.com/product/iso7046-zinc-nickel-alloy-phillips-head-countersunk-screws-with-flat-head-machine/) Countersunk & Flat-Head Machine Screws ### [ISO7046 Zinc-Nickel Alloy Phillips Head Countersunk Screws with Flat Head Machine Screws for Solar Energy Special High Salt Spray](https://engineeringhardware.com/product/iso7046-zinc-nickel-alloy-phillips-head-countersunk-screws-with-flat-head-machine/) Countersunk · 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