Skip to main content
Home / Screws / 304 Stainless Steel Extra Large Extra Long Full Thread Socket Head Cap Screw Cylinder Head Screw M3 M4 M5 M6 M8-M30

Attributes

Brand -
Category Standard Parts, Components & Industrial Consumables / Screws
Origin -
Material 304 Stainless Steel
Head Style Socket Head Cap (Cylinder)
Drive Type Hex Socket (Allen)
Thread Type Full Thread (Coarse)
Available Sizes M3, M4, M5, M6, M8, M10, M12, M16, M20, M24, M30
Finish Polished Silver
Strength Grade A2-70
Corrosion Resistance High (Suitable for damp environments)
Application Machinery, Automotive, Construction, DIY Projects
Package Content Assorted Kit or Bulk Pack (Selected at Checkout)

6 reviews

A

Anonymous

Mar 17, 2026

Rating: 5/5

Perfect for machinery repair

Used the M8 and M10 sizes to repair a conveyor belt mechanism. The hex socket fits perfectly with standard Allen keys, and the full thread provided excellent grip.

A

Anonymous

Mar 12, 2026

Rating: 4/5

Good variety but packaging could be better

The screws themselves are great quality and the threads are precise. However, the small sizes were all mixed together in one bag. Would prefer separate compartments for each size.

A

Anonymous

Mar 08, 2026

Rating: 5/5

Excellent quality stainless steel

These screws are exactly what I needed for my outdoor project. The 304 stainless steel feels robust and the finish is very clean. No signs of rust after a few weeks in the rain.

A

Anonymous

Mar 07, 2026

Rating: 5/5

Great value for bulk purchase

Bought the M4 and M5 assortment for general workshop use. The price per unit is unbeatable compared to local hardware stores. Will definitely buy again.

A

Anonymous

Mar 07, 2026

Rating: 5/5

Heavy duty and reliable

Needed extra long screws for a custom furniture build. These M6 extra-long variants were perfect. Very sturdy and the cylinder head looks professional.

A

Anonymous

Mar 07, 2026

Rating: 3/5

Decent but some heads were stripped

Most of the screws are fine, but I found about three in the pack where the hex socket was slightly deformed, making them hard to drive. The rest worked flawlessly.

5 FAQ

Q: Do you sell matching nuts and washers for this set?

A: Yes, we offer compatible 304 stainless steel hex nuts and flat washers in all corresponding sizes. Please check the 'Related Products' section on the product page.

Q: Can I return the item if I selected the wrong size?

A: Absolutely. As long as the items are unused and in original packaging, you can initiate a return within 30 days of delivery for a full refund or exchange.

Q: Are these screws suitable for marine environments?

A: While 304 stainless steel offers good corrosion resistance, for constant exposure to saltwater, we recommend our 316 stainless steel series for superior protection.

Q: Is there a certificate of material compliance included?

A: For bulk orders over 500 units, a material test report (MTR) can be provided upon request. For smaller kits, general specification sheets are available for download.

Q: What is the tensile strength of these M6 screws?

A: These screws are graded A2-70, which indicates a minimum tensile strength of 700 MPa.

Explore your interests

View More
All Categories
Best Seller (30)
New List (30)
Foldable Steel Tire Stone Removal Hook - Multi-Tool for Tire Repair, Stone Picking, and Emergency Window Breaking with Storage Bag

Foldable Steel Tire Stone Removal Hook - Multi-Tool for Tire Repair, Stone Picking, and Emergency Window Breaking with Storage Bag

$11.70

Integrated Catalytic Combustion Unit RCO Furnace - Exhaust Gas Treatment System with Activated Carbon Adsorption-Desorption and Catalytic Combustion

Integrated Catalytic Combustion Unit RCO Furnace - Exhaust Gas Treatment System with Activated Carbon Adsorption-Desorption and Catalytic Combustion

$231,249.00

Universal Waterproof and Sunproof Cover for E-Bike Charger with Outdoor Storage Box

Universal Waterproof and Sunproof Cover for E-Bike Charger with Outdoor Storage Box

$11.85

Baohong Paper Brick Watercolor Paper Pad, Medium/Coarse Texture, Square/Round Shapes for Painting, Sketching, and Cotton Pulp Practice

Baohong Paper Brick Watercolor Paper Pad, Medium/Coarse Texture, Square/Round Shapes for Painting, Sketching, and Cotton Pulp Practice

$28.00

Commercial Food Warmer Cabinet for Pies, Youtiao, Burgers, Egg Tarts, and Fried Chicken, Heating and Temperature-Controlled Display Case

Commercial Food Warmer Cabinet for Pies, Youtiao, Burgers, Egg Tarts, and Fried Chicken, Heating and Temperature-Controlled Display Case

$977.00

Masking Tape Spray Paint Shielding Paper for Art Students and Sketching - Non-bleeding, Residue-free, Hand-tearable, Shoe-safe

Masking Tape Spray Paint Shielding Paper for Art Students and Sketching - Non-bleeding, Residue-free, Hand-tearable, Shoe-safe

$1.00

Electric Scooter and Motorcycle Hook - Multi-Functional Storage Hanger for Delivery Bikes and Cargo Boxes

Electric Scooter and Motorcycle Hook - Multi-Functional Storage Hanger for Delivery Bikes and Cargo Boxes

$2.50

Huirui 420AB Fast-Drying Glue for Silicone - Bonds ABS, Stainless Steel, TPE, Rubber; High-Strength Instant Adhesive for Difficult Materials

Huirui 420AB Fast-Drying Glue for Silicone - Bonds ABS, Stainless Steel, TPE, Rubber; High-Strength Instant Adhesive for Difficult Materials

$36.00

Color Proofing Instrument Ink Mixing Tool Sample Making Machine

Color Proofing Instrument Ink Mixing Tool Sample Making Machine

$1,860.00

Variable Frequency Drive 0.75kW 2.6A Three-Phase 380V

Variable Frequency Drive 0.75kW 2.6A Three-Phase 380V

$1,430.00

2026 Spring PEP New Edition Primary English Grade 3 Volume 2 Four-Line Three-Grid Word Cards for Teachers, Open Class Competition Creative Blackboard Design, Teaching Contest Blackboard Strips and Teaching Aids

2026 Spring PEP New Edition Primary English Grade 3 Volume 2 Four-Line Three-Grid Word Cards for Teachers, Open Class Competition Creative Blackboard Design, Teaching Contest Blackboard Strips and Teaching Aids

$11.30

Cold Brew Yogurt Fermentation Equipment - Manual Old-Style Yogurt Processing and Filling Line

Cold Brew Yogurt Fermentation Equipment - Manual Old-Style Yogurt Processing and Filling Line

$113,050.00

Electric Spray Painting Pen Set for Babies and Toddlers, Non-Toxic Washable Watercolor Markers, Drawing Tool Kit Toy

Electric Spray Painting Pen Set for Babies and Toddlers, Non-Toxic Washable Watercolor Markers, Drawing Tool Kit Toy

$49.50

[Buy 2 Get 10% Off] Painted Double-Layer Wool Felt Mat for Calligraphy and Painting

[Buy 2 Get 10% Off] Painted Double-Layer Wool Felt Mat for Calligraphy and Painting

$7.48

Compact Home Range Hood, Portable USB Desktop Smoke Extractor for Living Room Hot Pot and BBQ Odor Removal

Compact Home Range Hood, Portable USB Desktop Smoke Extractor for Living Room Hot Pot and BBQ Odor Removal

$41.00

Office and Home Computer Cable Management Sleeve - Desktop Data Cord Organizer and PC Wire Collector

Office and Home Computer Cable Management Sleeve - Desktop Data Cord Organizer and PC Wire Collector

$6.50

Linear Bearing

Linear Bearing

$75.47

Thickened Aluminum Alloy Stainless Steel Floor Wire Raceway - Surface-Mounted Cable Cover Protector, Anti-Crush, Self-Adhesive Invisible Design

Thickened Aluminum Alloy Stainless Steel Floor Wire Raceway - Surface-Mounted Cable Cover Protector, Anti-Crush, Self-Adhesive Invisible Design

$2.13

Kids Foam Stamp Brushes - Mushroom-Tipped Painting Set for Kindergarten Art and Graffiti Projects

Kids Foam Stamp Brushes - Mushroom-Tipped Painting Set for Kindergarten Art and Graffiti Projects

$2.38

Heisidike HZL-32 Portable Stone Removal Hook for Car Tire Tread Cleaning

Heisidike HZL-32 Portable Stone Removal Hook for Car Tire Tread Cleaning

$9.28

Bixilage Cheese Processing Equipment – Curd Fermentation Machine for Stretchy Hand-Pulled Cheese Production Line

Bixilage Cheese Processing Equipment – Curd Fermentation Machine for Stretchy Hand-Pulled Cheese Production Line

$67,900.00

Essential Oil Soap Stamping Machine DIY Stamp Maker Semi-Auto Pneumatic Stampler Small Handmade Soap Equipment

Essential Oil Soap Stamping Machine DIY Stamp Maker Semi-Auto Pneumatic Stampler Small Handmade Soap Equipment

$2,173.00

Inverted Barrel Water Stand - Simple U-Shaped Thickened Holder for Purified Water Buckets with Dispenser Outlet

Inverted Barrel Water Stand - Simple U-Shaped Thickened Holder for Purified Water Buckets with Dispenser Outlet

$21.00

Qingling Pickup 2.8T Diesel Isuzu 4JB1-T1 Engine Turbocharger Pump Assembly

Qingling Pickup 2.8T Diesel Isuzu 4JB1-T1 Engine Turbocharger Pump Assembly

$1,502.00

Juli JL-499 Heat Resistant up to 150°C Instant Adhesive High Performance Low Whitening Transparent High-Temperature Fast-Drying Glue

Juli JL-499 Heat Resistant up to 150°C Instant Adhesive High Performance Low Whitening Transparent High-Temperature Fast-Drying Glue

$90.30

Stainless Steel Buffet Warmer with Hydraulic Lift - Commercial Electric Heating Chafing Dish

Stainless Steel Buffet Warmer with Hydraulic Lift - Commercial Electric Heating Chafing Dish

$882.00

Zhaobei New Felt Calligraphy Mat Anti-Pilling Painting Felt Chinese Painting Cloth Brush Character Calligraphy Felt Pad

Zhaobei New Felt Calligraphy Mat Anti-Pilling Painting Felt Chinese Painting Cloth Brush Character Calligraphy Felt Pad

$29.70

Fruit Picking Bucket with Shoulder Strap, Manual Fertilizer Spreader, Durable Rubber Harvest Container for Seeds and Chemicals

Fruit Picking Bucket with Shoulder Strap, Manual Fertilizer Spreader, Durable Rubber Harvest Container for Seeds and Chemicals

$26.57

Baohong Artist Grade Watercolor Pad - 100% Cotton Pulp, 300gsm, Glued on Four Sides, Available in 16K, 8K, 4K with Cold Press or Hot Press Texture

Baohong Artist Grade Watercolor Pad - 100% Cotton Pulp, 300gsm, Glued on Four Sides, Available in 16K, 8K, 4K with Cold Press or Hot Press Texture

$42.00

Commercial Brush Peeling Machine for Sweet Potatoes, Ginger, Taro, Mustard Greens, and Kohlrabi

Commercial Brush Peeling Machine for Sweet Potatoes, Ginger, Taro, Mustard Greens, and Kohlrabi

$15.90