Skip to main content
Home / Connectors and Fasteners / Weinai Grade 8.8 High-Strength Cup Head Socket Cap Bolts, Cylinder Head Screws, Studs M4 M5 M6 M8 M10-M20

Attributes

Brand -
Category Industrial Small Parts / Connectors and Fasteners
Origin -
Material Carbon Steel
Strength Class 8.8
Head Type Cylinder Head
Drive Style Internal Hex
Thread Standard Metric Coarse
Surface Finish Black Oxide
Compliance Standard DIN 912
Available Sizes M4 to M20
Package Contents Assorted Kit
Country of Origin China

5 reviews

A

Anonymous

Apr 04, 2026

Rating: 5/5

Quick Shipping

Packaged securely in a sturdy box. No rust or damage upon arrival.

A

Anonymous

Feb 17, 2026

Rating: 5/5

Solid Construction

Great for general mechanical assembly. The heads did not strip under torque.

A

Anonymous

Feb 15, 2026

Rating: 5/5

Reliable Fasteners

No stripping during installation. Used them on a high vibration motor mount.

A

Anonymous

Jan 31, 2026

Rating: 5/5

True to Size

Dimensions match the spec sheet perfectly. Very satisfied with the precision.

A

Anonymous

Jan 29, 2026

Rating: 4/5

Good Value

Quality is good for the price point. Shipping was slightly delayed but product is fine.

5 FAQ

Q: Do you sell matching nuts?

A: Yes, please check our related products section for compatible hex nuts.

Q: Is this suitable for outdoor use?

A: Black oxide offers mild resistance. We recommend additional coating for harsh environments.

Q: What key size for M8?

A: A 6mm hex key is required for M8 socket head cap screws.

Q: Can I return opened packages?

A: Please review our return policy details on the checkout page for specifics.

Q: What is the hardness rating?

A: Typically 22-32 HRC for Grade 8.8 carbon steel fasteners.

Explore your interests

View More
All Categories
Best Seller (30)
New List (30)
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

No-Drill Invisible Cable Organizer – Self-Adhesive Wire Fixer, Data Cable Clip, and Net Cable Management Solution

No-Drill Invisible Cable Organizer – Self-Adhesive Wire Fixer, Data Cable Clip, and Net Cable Management Solution

$6.90

Stone Landscape Sculpture Engraved Pebble Gate Stone Cornerstone Roadside Marker

Stone Landscape Sculpture Engraved Pebble Gate Stone Cornerstone Roadside Marker

$838.05

Kitchen Sink Organizer Rack, Dish Drying Rack, Multi-Function Countertop Storage Shelf for Washing and Placing Bowls

Kitchen Sink Organizer Rack, Dish Drying Rack, Multi-Function Countertop Storage Shelf for Washing and Placing Bowls

$55.70

New Hanging Kitchen Sink Strainer Basket, Multi-Function Colander for Washing Vegetables and Filtering Leftovers

New Hanging Kitchen Sink Strainer Basket, Multi-Function Colander for Washing Vegetables and Filtering Leftovers

$7.74

Sting Bite Relief Pen Electric Bug Bite Relief for Indoor

Sting Bite Relief Pen Electric Bug Bite Relief for Indoor

$60.14

Thickened 160g Gouache Paper 8K/4K for Beginners and Art Exam Students - Professional Art Painting Paper for Watercolor, Gouache, and Acrylic Creation and Practice

Thickened 160g Gouache Paper 8K/4K for Beginners and Art Exam Students - Professional Art Painting Paper for Watercolor, Gouache, and Acrylic Creation and Practice

$5.78

Pad Printing Ink Cup Sealing Ring Rubber Gasket Elastic Rubber Ink Cartridge O-Ring Silicone Ink Leak-Proof Eco-Friendly Ink Cup Seal

Pad Printing Ink Cup Sealing Ring Rubber Gasket Elastic Rubber Ink Cartridge O-Ring Silicone Ink Leak-Proof Eco-Friendly Ink Cup Seal

$9.70

Stainless Steel Walnut Kernel Peeling Machine - Pecan Physical Peeling Equipment, DDA Washing Unit, Nut Kernel Peeler

Stainless Steel Walnut Kernel Peeling Machine - Pecan Physical Peeling Equipment, DDA Washing Unit, Nut Kernel Peeler

$36,315.00

Daxiang Machinery Top-Flow Pillow Packaging Machine for Vegetables, Bread, Mooncakes, Cakes, Food, and Fruit Sealing

Daxiang Machinery Top-Flow Pillow Packaging Machine for Vegetables, Bread, Mooncakes, Cakes, Food, and Fruit Sealing

$35,475.00

50 Pcs Market Commodity Price Tag ers Advertising Tags Paper

50 Pcs Market Commodity Price Tag ers Advertising Tags Paper

$45.37

Fountain in the Rain by Kaoru Sudo, Mr. Chui Saxophone, Three-Piece Precise Transcription Service

Fountain in the Rain by Kaoru Sudo, Mr. Chui Saxophone, Three-Piece Precise Transcription Service

$37.00

No-Clean Airbrush Set Electric Spray Gun Mini Bottom-Feed Airbrush for Furniture Leather Repair Paint and Art

No-Clean Airbrush Set Electric Spray Gun Mini Bottom-Feed Airbrush for Furniture Leather Repair Paint and Art

$225.00

Rubber Cable Raceway Speed Bump for Ground Crossing

Rubber Cable Raceway Speed Bump for Ground Crossing

$15.05

Replacement Blade Holder and Rotating Wheel for Butter Tea Maker - Includes Waterproof Gasket; Compatible with Milk Separators and Switch Assemblies

Replacement Blade Holder and Rotating Wheel for Butter Tea Maker - Includes Waterproof Gasket; Compatible with Milk Separators and Switch Assemblies

$56.50

Commercial Hanging Roast Duck Warmer Crispy Pork Belly Insulation Box Stainless Steel Countertop Roasted Meat Heater Cooked Food Display Cabinet

Commercial Hanging Roast Duck Warmer Crispy Pork Belly Insulation Box Stainless Steel Countertop Roasted Meat Heater Cooked Food Display Cabinet

$317.00

2MM 3MM 4MM Natural Color-Gradient Amethyst Soccer-Cut Faceted Loose Beads - Semi-Finished Amethyst Cuts

2MM 3MM 4MM Natural Color-Gradient Amethyst Soccer-Cut Faceted Loose Beads - Semi-Finished Amethyst Cuts

$17.00

Educational Toys for Babies 0-3 Years - Newborn Rattle and Musical Stick for Boys and Girls (0-12 Months)

Educational Toys for Babies 0-3 Years - Newborn Rattle and Musical Stick for Boys and Girls (0-12 Months)

$12.80