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Metric 18-8 Stainless Steel Coupling Nuts

Made from 18-8 stainless steel, these metric coupling nuts have good chemical resistance and may be mildly magnetic. Also known as extension nuts, use them to connect and extend threaded rods.
For technical drawings and 3-D models, click on a part number.
Thread | Each | |||||
---|---|---|---|---|---|---|
Size | Pitch, mm | Lg., mm | Wd., mm | 1-9 | 10-Up | |
18-8 Stainless Steel | ||||||
M27 | 3 | 81 | 41 | 000000000 | 000000 | 000000 |
Metric Low-Strength Steel Coupling Nuts

Often referred to as extension nuts, use these to connect and extend threaded rods. They're about half the strength of medium-strength steel coupling nuts for use in light duty fastening applications.
Zinc-plated steel coupling nuts resist corrosion in wet environments.
Black-oxide steel coupling nuts have a dark surface color and are mildly corrosion resistant in dry environments.
For technical drawings and 3-D models, click on a part number.
Metric High-Strength Steel Coupling Nuts—Class 10

Often referred to as extension nuts, use these to connect and extend threaded rods. Made from Class 10 steel, they're about 25% stronger than medium-strength steel coupling nuts and comparable in strength to Class 10.9 bolts.
Zinc-plated steel nuts are corrosion resistant in wet environments.
For technical drawings and 3-D models, click on a part number.
Thread | Each | ||||||
---|---|---|---|---|---|---|---|
Size | Pitch, mm | Lg., mm | Wd., mm | Specifications Met | 1-9 | 10-Up | |
Zinc-Plated Steel—Class 10 | |||||||
M27 | 3 | 81 | 41 | DIN 6334 | 000000000 | 000000 | 000000 |