Engineered for reliable fastening, this M21x20mm brass hex head cap screw offers excellent corrosion resistance and non-magnetic properties. Its robust design ensures secure connections in demanding environments.
| Standard | ASME B18 |
| Material | Brass |
| Finish | Anodized |
| Grade | N/A |
| Size | M21 |
| Length | 20mm |
| Head Width | 21mm |
Trusted by engineers across multiple sectors, this M21x20mm brass hex head cap screw (21mm head width) is manufactured from high-grade brass, renowned for its superior corrosion resistance, excellent conductivity, and non-magnetic characteristics. This makes it an ideal choice for applications involving moisture, saltwater, or where electrical interference is a concern. The metric thread ensures compatibility with standard M21 nuts and tapped holes, providing a secure and durable mechanical joint for marine hardware, electrical components, and decorative architectural elements.
This component strictly adheres to the tolerances, material specifications, and quality benchmarks set by the world's leading industrial manufacturers.
1. Ensure the mating threads are clean and free of debris. 2. Hand-thread the screw to confirm proper engagement and alignment. 3. Use an appropriate wrench on the hex head to tighten to the required torque, avoiding over-tightening.
| Standard System | Designation |
|---|---|
| ISO Equivalent | ISO 898-1 / ISO 4014 |
| DIN Equivalent | DIN 931 / DIN 933 |
| Primary Standard | ASME B18 |
| Tensile Strength | Standard Commercial Spec |
| Yield Strength | Standard Commercial Spec |
| Hardness | Varies by specific batch |
| Copper (Cu) | 60.0 - 63.0% |
| Zinc (Zn) | Balance |
| Lead (Pb) | 2.5 - 3.7% |
| Bolt Size | Dry Torque (ft-lbs) | Lubricated Torque (ft-lbs) |
|---|---|---|
| M21 | Check Calculator | Reduce by 25% |
| Size / Type | Est. Weight (lbs/100) | Shipping Weight (kg) |
|---|---|---|
| M21 | Varies by dimension | Contact Sales |
| Environment | Rating |
|---|---|
| Indoor / Dry | Excellent |
| Outdoor / Exposed | Moderate |
| Marine / Saltwater | Not Recommended |
| Chemical / Acidic | Not Recommended |
| ❌ Mistake | ✅ Correct Approach |
|---|---|
| Using excessive force, leading to thread stripping or component damage. | Refer to torque specifications for the specific application or consult an engineer for recommended torque values. Always start by hand-threading. |
| Using the wrong tool size for the hex head, causing cam-out and potential damage to the fastener. | Utilize a correctly sized metric socket or wrench that fits snugly onto the hex head of the M21 screw. |
A: This Hex Head Cap Screw, Brass is manufactured from Brass.
A: Marine hardware and fittings, Electrical connectors and enclosures, Architectural fixtures and decorative elements.
Conversion factor: 1 ft-lb ≈ 1.356 Nm
| Status | Mating Component | Standard | Torque Spec | Engineering Notes |
|---|---|---|---|---|
| No verified compatibility data found for this component. | ||||