Black oxide is a conversion coating about 1–2 µm thick, usually oiled. It adds mild corrosion resistance and keeps dimensions exact, which matters on 10.9 and 12.9 parts — there is no hydrogen embrittlement risk.
In stock now: 1,589 lines; covering Screws (700), Washers & Retaining Rings (381), Set Screws (331), Socket Head Screws (327), DIN916 (309); priced from $0.0013 per piece. Every line is sold by the piece — one piece is a valid order.
Related values on the same axis
Anodised Black Black Nickel Plated Black Oxide (Hardened) Black Zinc Plated Blue Blue-White Zinc Plated Blue Zinc Plated Brass Plated Brushed
Product families covered
Screws 700 Washers & Retaining Rings 381 Set Screws 331 Socket Head Screws 327 DIN916 309 Self-Tapping & Drilling Screws 275 Self-Tapping Screws 275 Retaining Rings 229 ANSI/ASME B18.3SH( Knurled ) 217 Round Head With Washer Self-Tapping 149 DIN912 Plain & Spring Washer Assemblies 110 Anchors & Fastener Assemblies 110
Frequently asked
| Product | Diameter × Length | Material | Stock | Unit price | ||
|---|---|---|---|---|---|---|
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GB 895.2 External Wire Ring Φ50 70Mn Spring Steel
Black Oxide |
Φ50 | 70Mn Spring Steel | In stock | Log in to see prices | Log in to order |
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GB 895.1 Internal Wire Ring Φ50 70Mn Spring Steel
Black Oxide |
Φ50 | 70Mn Spring Steel | In stock | Log in to see prices | Log in to order |

