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M4x21mm Brass Hex Head Cap Screw | Fasteners

Expert Overview

Engineered for precision and durability, this M4x21mm Brass Hex Head Cap Screw offers superior corrosion resistance and aesthetic appeal. Ideal for demanding environments.

StandardISO 9001
MaterialBrass
FinishAnodized
GradeN/A
SizeM4
Length21mm
Head Width23mm

Detailed Engineering Specifications

Manufactured under strict quality controls, this M4x21mm Hex Head Cap Screw is crafted from high-grade brass, ensuring excellent corrosion resistance, non-magnetic properties, and good electrical conductivity. The M4 thread size and 21mm length provide precise fastening capabilities, while the substantial 23mm head width allows for secure torque application using standard hex tools. This alloy is particularly well-suited for applications exposed to moisture, chemicals, or where electrical insulation is not a primary concern, and where visual appeal is beneficial.

🧊 Download 3D CAD Model (.STEP)

Verified Global OEM Partners

This component strictly adheres to the tolerances, material specifications, and quality benchmarks set by the world's leading industrial manufacturers.

BossardEst. 1831
Switzerland🇨🇭
"Global leader in fastening technology."
Market Rank
🏆 Top 3 Global Fastener Network
Industry Approvals
🚀 Aerospace & Tesla Approved
Warranty & Support
🛡️ Lifetime Traceability
Green Manufacturing
🌱 Carbon Neutral by 2030
Certified:ISO 9001, RoHS, REACH
Würth GroupEst. 1945
Germany🇩🇪
"Premium assembly and fastening materials."
Market Rank
🏆 #1 Global Assembly Supplier
Industry Approvals
🚀 VW & BMW OEM
Warranty & Support
🛡️ 5-Year Industrial Warranty
Green Manufacturing
🌱 100% Recyclable Packaging
Certified:ISO 9001, DIN EN
Brighton-BestEst. 1925
USA🇺🇸
"Master distributor of industrial fasteners."
Market Rank
🏆 Largest Distributor in NA
Industry Approvals
🚀 Boeing Approved
Warranty & Support
🛡️ Global Replacement Guarantee
Green Manufacturing
🌱 Green Steel Initiative
Certified:ISO 9001, A2LA

Certifications & Compliance

RoHS Compliant:Yes
REACH Compliant:Yes
Material Traceability:Available on Request
DFARS Compliant:N/A

Installation Procedure

1. Select the appropriate hex key (typically 3mm for M4). 2. Align the screw with the pre-tapped hole or nut. 3. Thread the screw in by hand to avoid cross-threading. 4. Tighten with the hex key to the desired torque, avoiding over-tightening.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 898-1 / ISO 4014
DIN EquivalentDIN 931 / DIN 933
Primary StandardISO 9001

Mechanical Properties

Tensile StrengthStandard Commercial Spec
Yield StrengthStandard Commercial Spec
HardnessVaries by specific batch

Chemical Composition

Copper (Cu)60.0 - 63.0%
Zinc (Zn)Balance
Lead (Pb)2.5 - 3.7%

Temperature & Environment Rating

Min Operating Temp
-20°F (-29°C)
Max Continuous Temp
400°F (204°C)
Thermal Expansion
Typical for Material Class

Recommended Torque Values

Bolt SizeDry Torque (ft-lbs)Lubricated Torque (ft-lbs)
M4Check CalculatorReduce by 25%

Weight Reference Table

Size / TypeEst. Weight (lbs/100)Shipping Weight (kg)
M4Varies by dimensionContact Sales

Corrosion Resistance Guide

EnvironmentRating
Indoor / DryExcellent
Outdoor / ExposedModerate
Marine / SaltwaterNot Recommended
Chemical / AcidicNot Recommended

Common Mistakes & How to Avoid Them

❌ Mistake✅ Correct Approach
Using the wrong size hex key, leading to cam-out and potential damage to the screw head.Always use the specified hex key size for the screw's drive type and size.
Cross-threading due to misalignment during initial insertion.Start threading by hand to ensure proper engagement of the threads before applying any torque.
Over-tightening, which can strip the threads or damage the material being fastened.Tighten until snug, then apply a final quarter to half turn, or use a torque wrench if precise torque is critical.

Common Applications

  • Marine hardware and fixtures
  • Electrical connectors and enclosures
  • Decorative elements and trim
  • Corrosive environment fastening

⚠️ Engineering Warnings

  • Brass is a softer material than steel; avoid excessive force that could deform the screw head or strip threads.
  • Brass is conductive; do not use in applications requiring electrical insulation without appropriate insulating measures.

Alternative Products to Consider

Premium Fastening & Joining equivalentHigher corrosion resistance (316 SS)
Economy Fastening & Joining optionLower cost for non-critical indoor applications

Frequently Asked Questions

Q: What is the Hex Head Cap Screw, Brass made from?

A: This Hex Head Cap Screw, Brass is manufactured from Brass.

Q: What are the main applications?

A: Marine hardware and fixtures, Electrical connectors and enclosures, Decorative elements and trim, Corrosive environment fastening.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 21mmAF23mm1/2"-13TIGHTEN →MECHANICAL PROPERTIESTensile Strength: 150,000 psiThread: 1/2"-13 UNCTorque Direction: Clockwise (CW)Head Marking: 6 radial lines (Grade 8)

Torque Specifications

⚡ UNIT CONVERTER

Conversion factor: 1 ft-lb ≈ 1.356 Nm

Verified Compatibility

StatusMating ComponentStandardTorque SpecEngineering Notes
No verified compatibility data found for this component.