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Black High Strength Hex Socket Bolt/Galvanized / Stainless Steel Round Head Hex Socket Bolt

Updated 2026-11-04 · Markdown version

Model no. M3-M20

US$0.012 – 0.12 / piece

MOQ 5,000 pieces · Final price confirmed in your quote

Material: Stainless Steel
Head Style: Round
Standard: DIN, ANSI, GB, JIS, BSW, GOST
Grade: 12.9
Finish: Polishing
Carbon Steel Grade: 4.8 6.8 8.8 10.9 12.9
Bolt Material: Carbon Steel, Stainless Steel, High Carbon Steel
Surface Coating: Galvanized / Hot DIP Galvanized / Black

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	Round Head
Model NO.	M3-M20
Connection	Hinged Bolts
Head Style	Round
Standard	DIN, ANSI, GB, JIS, BSW, GOST
Grade	12.9
Application	Machinery, Chemical Industry, Environmental, Building
Finish	Polishing
Carbon Steel Grade	4.8 6.8 8.8 10.9 12.9
Bolt Material	Carbon Steel, Stainless Steel, High Carbon Steel
Surface Coating	Galvanized / Hot DIP Galvanized / Black
Transport Package	Export Packing
Specification	Can be customized
Origin	Hebei
HS Code	7318151090
Production Capacity	100000000
Category	Structural & Heavy Hex Bolts

Technical parameters

specification table
Stainless steel hexagon bolt
Screw diametet ( d)	Coarse thread distance ( P )	Head outside diameter (dk)	Head thickness (k)	Hexagon opposite side (s)	Hexagonal hole depth ( t )
max	min	max	min	max	min	min
:mm
M1.4	0.3	2.74	2.46	1.4	1.26	1.36	1.32	0.6
M1.6	0.35	3.14	2.86	1.6	1.46	1.56	1.52	0.7
M2	0.4	3.98	3.62	2	1.86	1.56	1.52	1
M2.5	0.45	4.68	4.32	2.5	2.36	2.06	2.02	1.1
M3	0.5	5.68	5.32	3	2.86	2.58	2.52	1.3
M4	0.7	7.22	6.78	4	3.82	3.08	3.02	2
M5	0.8	8.72	8.28	5	4.82	4.095	4.02	2.5
M6	1	10.22	9.78	6	5.7	5.14	5.02	3
M8	1.25	13.27	12.73	8	7.64	6.14	6.02	4
M10	1.5	16.27	15.73	10	9.64	8.175	8.025	5
M12	1.75	18.27	17.73	12	11.57	10.18	10.03	6
M14	2	21.33	20.67	14	12.57	12.21	12.03	7
M16	2	24.33	23.67	16	15.57	14.21	14.03	8
M18	2.5	27.33	26.67	18	17.57	14.21	14.03	9
M20	2.5	30.33	19.67	20	19.48	17.23	17.05	10
M22	2.5	33.39	32.61	22	21.48	17.23	17.05	11
M24	3	36.36	35.61	24	23.48	19.28	19.07	12
M27	3	40.39	39.61	27	26.48	19.28	19.07	13.5
M30	3.5	45.39	44.61	30	29.48	22.28	22.07	15.6

Description

Black High Strength Hex Socket Bolt/Galvanized / Stainless Steel Round Head Hex Socket Bolt is part of our structural & heavy hex bolts range (Bolts).

Key details

Type: Round Head
Standard: DIN, ANSI, GB, JIS, BSW, GOST
Material: Stainless Steel
Grade: 12.9
Head Style: Round
Finish: Polishing
Connection: Hinged Bolts
Application: Machinery, Chemical Industry, Environmental, Building

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 5,000 pieces at US$0.012 – 0.12 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 Black High Strength Hex Socket Bolt/Galvanized / Stainless Steel Round Head Hex Socket Bolt?

The listed minimum order is 5,000 pieces, at US$0.012 – 0.12 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 Black High Strength Hex Socket Bolt/Galvanized / Stainless Steel Round Head Hex Socket Bolt?

Type: Round Head; Standard: DIN, ANSI, GB, JIS, BSW, GOST; Material: Stainless Steel; Grade: 12.9; Head Style: Round; Finish: Polishing. 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 structural & heavy hex bolts are available?

The Structural & Heavy Hex Bolts category lists 2,565 products in different sizes, materials and finishes: https://engineeringhardware.com/fastener-products/bolts/structural-heavy-hex-bolts/

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

More about us → · Request a sample or custom quote →

Request a quote for this product

US$0.012 – 0.12MOQ 5,000 piecesGet a quote WA