Material specification page for low and high cap (acorn) nuts, inch in A2 Stainless Steel. Covers the grade designation (ISO 3506 group A2 (304 / 1.4301), commonly supplied A2-70), corrosion and magnetic behavior, comparable grades and their trade-offs, and the sizes available to SAE J483.
Why Choose A2 Stainless Steel for Low and High Cap (Acorn) Nuts, Inch
The most common stainless group for indoor and general outdoor fasteners. For low and high cap (acorn) nuts, inch, this matters when good general corrosion resistance is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 3506 group A2 (304 / 1.4301), commonly supplied A2-70 |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C, subject to the property class and the joint |
| Corrosion characteristic | Good general corrosion resistance |
Corrosion Behavior in Service
A2 (304) gives excellent atmospheric and most-water corrosion resistance and is the most common stainless for Low and High Cap (Acorn) Nuts, Inch in indoor and general outdoor service. In chloride-bearing environments (marine air, road salt, swimming pools) consider stepping up to A4 (316).
Comparable Grades
For Low and High Cap (Acorn) Nuts, Inch, the alternative stainless grade is A4 (316). The practical dividing line is chlorides: A2 (304) is fine until salt is involved, and A4 (316) exists for the cases where it is — coastal, marine and road-salt service. Neither reaches the strength of a plated class 8.8 or 10.9 fastener.
Using Stainless Fasteners in Aluminum
Expect the aluminum to corrode, not the fastener — stainless sits higher in the galvanic series, so the aluminum is the one that gives up material. A small fastener in a thick section spreads the loss over a large area and is usually fine; a large fastener in thin sheet concentrates it and is not. Keep water out of the joint, or isolate the two metals with a nylon or coated washer and a sealant.
Sizes of Low and High Cap (Acorn) Nuts, Inch Available in A2 Stainless Steel
| Size | Type | Threads per inch | Width across flats s (in) | A (in) | Nut height m (in) | Q (in) | U (in) | Reference standard |
|---|---|---|---|---|---|---|---|---|
| #6 | Low cap nuts | 32 | 0.312 | 0.3 | 0.34 | 0.16 | 0.16 | SAE J483 |
| #8 | Low cap nuts | 32 | 0.312 | 0.3 | 0.34 | 0.16 | 0.16 | SAE J483 |
| #10 | Low cap nuts | 24 | 0.375 | 0.36 | 0.41 | 0.19 | 0.19 | SAE J483 |
| #12 | Low cap nuts | 24 | 0.375 | 0.36 | 0.41 | 0.19 | 0.22 | SAE J483 |
| 1/4" | Low cap nuts | 20 | 0.438 | 0.41 | 0.47 | 0.22 | 0.25 | SAE J483 |
| 5/16" | Low cap nuts | 18 | 0.5 | 0.47 | 0.53 | 0.25 | 0.31 | SAE J483 |
| 3/8" | Low cap nuts | 16 | 0.562 | 0.53 | 0.62 | 0.28 | 0.38 | SAE J483 |
| 7/16" | Low cap nuts | 14 | 0.625 | 0.59 | 0.69 | 0.31 | 0.44 | SAE J483 |
| 1/2" | Low cap nuts | 13 | 0.75 | 0.72 | 0.81 | 0.38 | 0.5 | SAE J483 |
| 9/16" | Low cap nuts | 12 | 0.875 | 0.84 | 0.94 | 0.44 | 0.56 | SAE J483 |
| 5/8" | Low cap nuts | 11 | 0.938 | 0.91 | 1 | 0.47 | 0.62 | SAE J483 |
| 3/4" | Low cap nuts | 10 | 1.062 | 1.03 | 1.16 | 0.53 | 0.75 | SAE J483 |
| 7/8" | Low cap nuts | 9 | 1.25 | 1.22 | 1.36 | 0.62 | 0.88 | SAE J483 |
| 1" | Low cap nuts | 8 | 1.438 | 1.41 | 1.55 | 0.72 | 1 | SAE J483 |
| 1 1/8" | Low cap nuts | 7 | 1.625 | 1.59 | 1.75 | 0.81 | 1.12 | SAE J483 |
| 1 1/4" | Low cap nuts | 7 | 1.812 | 1.78 | 1.95 | 0.91 | 1.25 | SAE J483 |
| #6 | High cap nuts | 32 | 0.312 | 0.3 | 0.42 | 0.17 | 0.19 | SAE J483 |
| #8 | High cap nuts | 32 | 0.312 | 0.3 | 0.42 | 0.17 | 0.19 | SAE J483 |
| #10 | High cap nuts | 24 | 0.375 | 0.36 | 0.52 | 0.2 | 0.25 | SAE J483 |
| #12 | High cap nuts | 24 | 0.375 | 0.36 | 0.52 | 0.2 | 0.28 | SAE J483 |
| 1/4" | High cap nuts | 20 | 0.438 | 0.41 | 0.59 | 0.23 | 0.31 | SAE J483 |
| 5/16" | High cap nuts | 18 | 0.5 | 0.47 | 0.69 | 0.28 | 0.38 | SAE J483 |
| 3/8" | High cap nuts | 16 | 0.562 | 0.53 | 0.78 | 0.31 | 0.47 | SAE J483 |
| 7/16" | High cap nuts | 14 | 0.625 | 0.59 | 0.88 | 0.34 | 0.53 | SAE J483 |
| 1/2" | High cap nuts | 13 | 0.75 | 0.72 | 1.03 | 0.42 | 0.62 | SAE J483 |
| 9/16" | High cap nuts | 12 | 0.875 | 0.84 | 1.19 | 0.48 | 0.69 | SAE J483 |
| 5/8" | High cap nuts | 11 | 0.938 | 0.91 | 1.28 | 0.53 | 0.78 | SAE J483 |
| 3/4" | High cap nuts | 10 | 1.062 | 1.03 | 1.45 | 0.59 | 0.94 | SAE J483 |
| 7/8" | High cap nuts | 9 | 1.25 | 1.22 | 1.72 | 0.7 | 1.09 | SAE J483 |
| 1" | High cap nuts | 8 | 1.438 | 1.41 | 1.97 | 0.81 | 1.25 | SAE J483 |
Dimensions are independent of the material: every size above is available in A2 Stainless Steel.
Custom manufacturing · Made to drawing
Need this nut in a grade that is not listed?
A2 Stainless Steel is one of the grades the catalog describes. Height and across-flats are the two most often changed — a thinner nut for clearance, a larger hex for a tool that is already on the line. Made by cold heading or tapping.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
