Product and application brief
Machine screws are selected for a defined mating thread in a nut or tapped component. Identify the thread system and the complete head and drive arrangement rather than relying on a photograph. This directory entry focuses on ordinary machine screw heads; socket and internal-drive screws have a separate purchasing entry.
Head and drive options
Identify pan, countersunk or another specified head and its cross, slotted or other drive. Head diameter, height, recess and bearing surface affect the available assembly space. A head name alone does not define the product.
Mating thread and length
Specify metric or inch thread, pitch, tolerance and required threaded length. State the length measurement convention, especially for countersunk heads. Supply the mating-hole or nut reference where fit is important.
Keep different versions separate
List head, drive, material and finish variants as separate order lines. Do not substitute a pointed self-tapping screw for a machine screw in a tapped hole without approval.
Specification checklist for quotation
Provide the required specification and quantity with units. These inputs are not a guaranteed stock range or a product approval.
| Requirement | What to specify |
|---|---|
| Reference | Exact standard and edition or controlled drawing number/revision |
| Head / drive | Head form, dimensions, drive type and recess requirement |
| Thread / length | System, diameter, pitch, tolerance, length convention and threaded length |
| Mating part | Nut or tapped-hole reference, engagement and clearance requirements |
| Material / finish | Material and specified mechanical properties, coating and finished thread fit |
| Order | Quantity with units by size, inspection documents, packing and destination |
Common purchasing questions
Are machine screws and self-tapping screws interchangeable?
No automatic substitution should be assumed. A mating machine thread and a thread-forming or thread-cutting arrangement have different requirements. Send the approved connection specification.
Can I send only a head photograph?
A photograph helps identification but does not define thread, dimensions or material. Add a drawing or complete reference and mark unresolved requirements.
Prepare your order brief
Attach the complete product reference or a controlled drawing with revision. List quantities and units for each size, material and finish; include the destination, packing and document requirements. Mark missing or unresolved items for review. Supply scope and any exceptions are confirmed for the actual quotation.
Related screw types
Prepare the specification
Technical context
Reference checked 4 October 2026 for terminology and selection context. Third-party products, specifications and approvals are not FastenerBridge supply or certification claims. Final requirements follow the selected product reference and approved drawing.