---
title: "Ss321 Ss321h DIN7991 Hexagon Socket Countersunk Head Cap Screw"
description: "Ss321 Ss321h DIN7991 Hexagon Socket Countersunk Head Cap Screw — Countersunk & Flat-Head Machine Screws. MOQ 300 pieces, US$0.66 – 1.20."
url: https://engineeringhardware.com/product/ss321-ss321h-din7991-hexagon-socket-countersunk-head-cap-screw/
source: Engineering Hardware & Fasteners
---

# Ss321 Ss321h DIN7991 Hexagon Socket Countersunk Head Cap Screw

[![Ss321 Ss321h DIN7991 Hexagon Socket Countersunk Head Cap Screw](https://img.engineeringhardware.com/Ss321-Ss321h-DIN7991-Hexagon-Socket-Countersunk-Head-Cap-Screw.webp)](https://img.engineeringhardware.com/Ss321-Ss321h-DIN7991-Hexagon-Socket-Countersunk-Head-Cap-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/ss321-ss321h-din7991-hexagon-socket-countersunk-head-cap-screw.md)

Model no. **SS321-DIN7991-M8X40**

| **US$1.20**300–999 pieces | **US$0.96**1,000–1,999 pieces | **US$0.72**2,000–4,999 pieces | **US$0.66**5,000+ pieces |
| --- | --- | --- | --- |

MOQ 300 pieces · Final price confirmed in your quote

- **Material:** Stainless Steel
- **Head Style:** Hexagonal
- **Standard:** DIN, ANSI, ISO
- **Grade:** Ss321/1.4541
- **Finish:** Passivation
- **Price for The Size:** M12X50
- **Packing:** Small Box
- **Length:** 10-1000mm ; 1/2"-40"

Get a quote [WhatsApp](https://wa.me/8615999653684?text=Hi%20Engineering%20Hardware%20%26amp%3B%20Fasteners%2C%20I%20would%20like%20a%20quote%20for%3A%20Ss321%20Ss321h%20DIN7991%20Hexagon%20Socket%20Countersunk%20Head%20Cap%20Screw%20%E2%80%94%20https%3A%2F%2Fengineeringhardware.com%2Fproduct%2Fss321-ss321h-din7991-hexagon-socket-countersunk-head-cap-screw%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

| Customization | Available |
| --- | --- |
| Material | Stainless Steel |
| Type | Hexagon Head |
| Model NO. | SS321-DIN7991-M8X40 |
| Connection | Common Bolt |
| Head Style | Hexagonal |
| Standard | DIN, ANSI, ISO |
| Grade | Ss321/1.4541 |
| Application | Building |
| Finish | Passivation |
| Price for The Size | M12X50 |
| Marking | ID+Grade |
| Packing | Small Box |
| Certificates | En10204-3.1b |
| How to Make | by Cold Forge |
| Transport Package | CTN First, Then in Pallet |
| Specification | M6-64 |
| Origin | Jiangsu, China |
| HS Code | 7318150000 |
| Production Capacity | 10 Tons /Month |
| Hexagon socket | facilitates tightening and untightening with an Allen key. Metric thread: available in metric ISO thread from M3 to M24 to suit different applications. |
| Length | 10-1000mm ; 1/2"-40" |
| Washers | 100 pcs, Nut: 50 pcs ,Bolt and Studs:10 pcs |
| Category | [Countersunk & Flat-Head Machine Screws](https://engineeringhardware.com/fastener-products/screws/countersunk-flat-head-machine-screws/) |

## Technical parameters

| Name | SS321 socket countersink screw |
| --- | --- |
| Standard | DIN7991,ISO10642 |
| Size Range | M5-M64 or non-standard as requested |
| Finish | Bright&Clean |
| Marking | HT&FST or customization |
| Material | SS321,1.4541, UNS S32100 |
| Grade | Grade 70,Grade 8T |
| Certificates | EN10204-3.1B |
| Non-standards | OEM is available, according to drawing or samples |
| Samples | Samples available |
| Package | Bulk in box and then in cartons, then on pallets, or according to customers' requirement. |
| Payment | T/T,Western Union |

| GRADE | UNS | W.Nr |
| --- | --- | --- |
| SS321 | S32100 | 1.4541 |

| Alloy | % | Ni | Cd | C | Mn | Si | S | Ti | P |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 321 | Min. | 9 | 17 |  |  |  |  | 5C |  |
| Max. | 12 | 19 | 0.08 | 2.0 | 1.0 | 0.03 | 0.7 | 0.035 |  |

| Density | 7.93 g/cm³ |
| --- | --- |
| Melting point | 1398~1446 ºC |

| Standard | DIN,ASME,SIO,JIS.BS.NFE,GOST |
| --- | --- |
| Size Range | Diameter M5 - M64 ; 1/4"- 2 1/2 Length:10-1000mm ; 1/2"-40" |
| Material | SS304 ,316,316L ,316LN,316 Lmod,316Ti,317L, 317LN, 321,310S, 904L 254SMO AL-6XN,1.4529 |
| Duplex 2205/2507 |  |
| Hastelloy C4, C22 , C276 , C2000, B2, B3 , G3 , G30 , Hastelloy X 2.4600 , 2.4602 , 2.4603 , 2.4610 , 2.4617 , 2.4619, 2.4665 , 2.4675 , 2.4819 |  |
| Inconel600, 601 , 617 , 625 , 690 , 718 , 725 , X750 2.4669 , 2.4668 , 2.4816 , 2.4856 , 2.4851 , 2.4663 , 2.4642 |  |
| Incoloy800/800H/800HT, Incoloy825 , 90 1, 925 , 926 , 1.4958 , 2.4662 , 1.4529 , 1.4876 , 2.4858 , 1.4959 |  |
| Monelk500, Monel400; 2.4360 , 2.4375 |  |
| Titanium Alloy GR2/5/7, 3.7035, 3.7165 , 3.7235 |  |
| Urea steel 724L ,725LN ; 1.4435 , 1.4466 |  |
| Alloy20, Alloy28, Alloy31, Alloy 286,Alloy 80A(nimonic 80A) 2.4660 , 1.4563 , 1.4562 , 1.4980 , 2.4952 |  |
| Product range | Bolt , U bolt , Studs , Threaded Bar , Nut , Washers ,Machining Parts |
| Marking | According to client's requirements ( OEM ) |
| MOQ | Washers : 100 pcs, Nut: 50 pcs ,Bolt and Studs:10 pcs |
| Sample policy | sample can be provided in free If we have stock,and the buyer pay the freight cost. |
| Sample time | 7-10 days about |
| In stock items | SS304/316 Bolt , Nut and washers M6-20 |
| DIN7967 Pal nut M6-20 |  |
| Titanium Alloy bolt , nut , washers M6-20 |  |
| Some other sizes may have stock. |  |
| One stop purchase | We Will help you to realise one stop purchasing.Our salesman have more than 18 years experience in trading |

## Description

Ss321 Ss321h DIN7991 Hexagon Socket Countersunk Head Cap Screw is part of our countersunk & flat-head machine screws range (Screws).

### Key details

- **Type:** Hexagon Head
- **Standard:** DIN, ANSI, ISO
- **Material:** Stainless Steel
- **Grade:** Ss321/1.4541
- **Length:** 10-1000mm ; 1/2"-40"
- **Head Style:** Hexagonal
- **Finish:** Passivation
- **Connection:** Common Bolt

Available configurations include material, head style, standard, grade and finish. Custom sizes, threads, materials, grades, platings and packaging can be quoted on request.

### Ordering through Engineering Hardware & Fasteners

Minimum order is 300 pieces at US$0.66 – 1.20 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 Ss321 Ss321h DIN7991 Hexagon Socket Countersunk Head Cap Screw?

The listed minimum order is 300 pieces, at US$0.66 – 1.20 per piece. Smaller trial quantities or samples can be requested in your inquiry; Engineering Hardware & Fasteners confirms what is possible for your size.

### How does the price change with quantity?

Volume pricing: US$1.20 for 300–999 pieces; US$0.96 for 1,000–1,999 pieces; US$0.72 for 2,000–4,999 pieces; US$0.66 for 5,000+ pieces. Final prices depend on size, material, finish and packing and are confirmed in your quote.

### What are the main specifications of Ss321 Ss321h DIN7991 Hexagon Socket Countersunk Head Cap Screw?

Type: Hexagon Head; Standard: DIN, ANSI, ISO; Material: Stainless Steel; Grade: Ss321/1.4541; Length: 10-1000mm ; 1/2"-40"; Head Style: Hexagonal. The full specification table and any technical parameter tables are listed on this page.

### Can this product be customized (OEM)?

Listed configurations include material, head style, standard, grade and finish. 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

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Production floor

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Inspection bench

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Sorting & packing

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Parts warehouse

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Sample review

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Sales office

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## Request a quote for this product

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