Product Description
2-56 UNC A2 Stainless Steel Countersunk Slotted Machine Screws
These No.2-56 UNC machine screws are manufactured from A2 stainless steel and feature a flat countersunk head with a slotted drive. The head seats flush within a correctly prepared countersink, making them suitable for small components and assemblies requiring a smooth surface.
The imperial UNC thread has 56 threads per inch and fits matching 2-56 UNC nuts or tapped holes. The listed overall length is 5/8", measured including the countersunk head.
Specifications
| Product type | Countersunk slotted head machine screw |
|---|---|
| Material | A2 stainless steel |
| Thread designation | No.2-56 UNC |
| Nominal thread diameter | 0.086" (approximately 2.184mm) |
| Threads per inch | 56 TPI |
| Listed length | 5/8" (15.875mm) |
| Head style | Flat countersunk |
| Drive | Slotted, for a correctly fitting flat-blade screwdriver |
| Head diameter guide | 0.144"–0.162" (approximately 3.66–4.11mm) |
| Head height guide | 0.051" (approximately 1.30mm) |
| Length measurement | Overall length, including the countersunk head |
Head dimensions are provided as a guide. Manufacturing tolerances apply; check critical dimensions before ordering.
Key Features
- A2 stainless steel construction for corrosion resistance.
- No.2-56 UNC imperial thread with 56 threads per inch.
- Countersunk head for flush seating in a matching countersink.
- Traditional slotted screwdriver drive.
- Listed 5/8" overall length.
Typical Applications
Suitable for small equipment assemblies, instrument covers, model engineering, restoration and repairs requiring No.2-56 UNC countersunk machine screws.
Installation
Use with matching 2-56 UNC nuts or tapped holes and a countersink suited to the screw head. Choose a flat-blade screwdriver that properly fills the slot and tighten carefully to the assembly specification. Keep threads clean and use an appropriate anti-galling lubricant where required.
Ordering
Select the required pack quantity from the available options. The listed screw length is 5/8", including the head. No.2 is an imperial screw size and does not mean M2.
Standards
- ASME B18.6.3 – inch-series machine screw dimensional reference.
- ASME B1.1 – Unified inch screw threads, including UNC.
