Product Description
1/4″-28 UNF A2 Stainless Steel Hexagon Set Screws
These 1/4″ UNF A2 stainless steel hexagon set screws feature a fully threaded shank and a standard 28 threads-per-inch Unified National Fine thread. The fine thread provides more thread engagement per unit of length than the corresponding UNC size and allows finer adjustment in suitable assemblies.
The 7/16″ external hexagon head allows installation using a standard imperial spanner or socket. Manufactured from A2 stainless steel, these screws provide good resistance to everyday corrosion and are suitable for machinery, automotive work, restoration, fabrication and general imperial fastening applications.
Product Details
- Thread size: 1/4″-28 UNF
- Thread series: Unified National Fine
- Threads per inch: 28 TPI
- Material: A2 stainless steel
- Head style: External hexagon head
- Spanner size: 7/16″
- Nominal head height: 5/32″
- Thread coverage: Fully threaded
- Available lengths: 1/2″ to 1 1/2″
- Length measurement: From beneath the head
Available Sizes
| Thread Size | Length | Width Across Flats | Nominal Head Height | Threads Per Inch |
|---|---|---|---|---|
| 1/4″ UNF | 1/2″ | 7/16″ | 5/32″ | 28 TPI |
| 1/4″ UNF | 5/8″ | 7/16″ | 5/32″ | 28 TPI |
| 1/4″ UNF | 3/4″ | 7/16″ | 5/32″ | 28 TPI |
| 1/4″ UNF | 1″ | 7/16″ | 5/32″ | 28 TPI |
| 1/4″ UNF | 1 1/4″ | 7/16″ | 5/32″ | 28 TPI |
| 1/4″ UNF | 1 1/2″ | 7/16″ | 5/32″ | 28 TPI |
Screw length is measured from beneath the hexagon head to the end of the threaded shank.
Benefits of UNF Fine Threads
- Finer adjustment than the equivalent UNC thread
- More engaged threads over the same axial distance
- Commonly used in automotive and precision engineering assemblies
- Suitable for matching 1/4″-28 UNF nuts and tapped holes
Benefits of A2 Stainless Steel
- Good resistance to moisture and atmospheric corrosion
- Suitable for many indoor and general outdoor applications
- No protective zinc coating to chip or wear away
- Clean appearance suitable for exposed assemblies
- Fully threaded design provides maximum adjustment and engagement
Typical Applications
- Automotive and motorcycle restoration
- Machinery and imperial equipment
- Engineering and precision assemblies
- Brackets, panels and equipment enclosures
- Fabrication and workshop projects
- General maintenance and repair work
Installation Guidance
Confirm that the mating nut or tapped hole has a 1/4″-28 UNF thread. These screws must not be confused with 1/4″-20 UNC fasteners, which have a coarser and incompatible thread.
Install using a correctly fitting 7/16″ imperial spanner or socket. Stainless steel threads can gall or seize when assembled quickly, without lubrication or under high tightening pressure. A suitable anti-seize compound may be beneficial where repeated assembly is expected.
A2 stainless steel is suitable for many general applications but may not be appropriate for prolonged exposure to seawater, salt spray or strongly chlorinated environments. A4 stainless steel should be considered for demanding marine and chloride-rich conditions.
Please select the required screw length and pack quantity from the options provided.
