From our factory in China, I deliver hexagonal keys 4mm that stand up to heavy duty use. As a long-time Manufacturer, I know what B2B buyers need: reliable supply, consistent tolerances, and fast response. These hex keys 4mm are crafted from premium steel, heat-treated for hardness, and finished with corrosion-resistant coating. The short-arm design boosts torque without twisting, and the long arm gives better reach for assembly in tight spaces. I offer strict QC checks, right from incoming material to final inspection. You can count on stable monthly output and flexible packaging to suit your inventory. MOQ is modest for new customers, and lead time is short for urgent projects. Whether you need customization, different lengths, or handle colors, I can accommodate. If you want a trustworthy China manufacturer partner for hex keys 4mm supply, I’m here to help.
The 4 mm hex key is designed for demanding assemblies in electronics, automotive, and machinery. Precision-ground tips and chamfered noses ensure clean engagement, reducing slip and wear. Made from hardened alloy steel and chrome-plated for corrosion resistance, it maintains stability across cycles. As a standard DIN 911 size, it delivers reliable torque transfer and access in tight spaces. Global buyers rely on consistent supply, traceability, and responsive service. This hex key line is produced under strict quality controls, with material verification and final dimensional checks. We offer scalable packaging, flexible lead times, and finishes or certificates to support just-in-time purchasing and diversified markets.
| Batch | Origin Region | Material Grade | Hardness (HRC) | Tensile Strength (MPa) | Yield Strength (MPa) | Dimensional Tolerance (mm) | Surface Roughness Ra (µm) | Finishing/Coating | ISO Certification | Defect Rate (%) | Production Efficiency (%) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| B-001 | Europe | 4140+Quenched | 52 | 1100 | 980 | ±0.03 | 0.9 | Black Oxide | ISO 9001:2015 | 0.08% | 96% |
| B-002 | Asia-Pacific | CK-45 | 50 | 980 | 860 | ±0.04 | 1.0 | Zinc | ISO 9001:2015 | 0.12% | 95% |
| B-003 | North America | 1045 | 53 | 1000 | 880 | ±0.025 | 0.8 | Plain | ISO 9001:2015 | 0.05% | 97% |
| B-004 | Europe | S2 Tool Steel | 54 | 1070 | 900 | ±0.02 | 0.75 | Chrome | ISO 9001:2015 | 0.04% | 98% |
| B-005 | Asia-Pacific | 4140 | 51 | 950 | 780 | ±0.03 | 1.2 | Black Oxide | ISO 9001:2015 | 0.09% | 94% |
| B-006 | North America | S2 | 52 | 1020 | 860 | ±0.03 | 0.9 | Zinc | ISO 9001:2015 | 0.03% | 97% |