MS24667 and MS24671 flat countersunk socket cap screws
82-degree flat countersunk socket head cap screws, UNC-3A, #4 through 3/4 in., in alloy steel or stainless.
MS24667, MS24671, machined to the standard.
Despite the socket-head name, these are flush-mounting screws: an 82-degree flat countersunk head with a hex socket. MS24667 is heat-treated alloy steel, zinc coated or cadmium plated, with an optional self-locking element. MS24671 is non-magnetic austenitic stainless, passivated. Both were cancelled in 1998 and are now NASM24667 and NASM24671.
- Machined from certified bar to the standard; no hot heading
- AS9100D and ISO 9001:2015 quality system; CAGE 8HH90
- DFARS-compliant material available on request
- No minimum quantity; prototype through production
- Material test reports and certificates of conformance with the order
Send the full part number with the dash number and code letters, the quantity, the required delivery and the documentation your purchase order calls for.
MS24667, MS24671 at a glance
| Detail | Specification |
|---|---|
| Standard | MS24667 and MS24671, now NASM24667 and NASM24671 (active) |
| Title | Screw, Cap, Socket Head, Flat Countersunk, 82 deg |
| Material | MS24667: alloy steel per FF-S-86, zinc coated (Z) or cadmium plated. MS24671: austenitic stainless, passivated |
| Thread | UNC-3A, #4-40 through 3/4-10 |
| Strength | MS24671: 80,000 psi minimum through 5/8, 70,000 psi over 5/8 |
| Typical use | Flush-mounted machinery and equipment hardware |
Part numbers covered: MS24667 (alloy steel), MS24671 (corrosion-resisting steel). Reference only; the current revision of the standard on your order governs.
Reading the part number.
| Element | Meaning |
|---|---|
| Dash number | Thread size and length from Table I |
| Z after the dash | Zinc coating (MS24667) |
| L after the dash | Self-locking element (MS24667) |
How Cyclone makes them
Bar stock certified to the material specification is cut, turned and threaded to the standard’s dimensions, with drilled heads or shanks and head markings as the part number requires. Plating and locking elements are applied through partner facilities to the standard.
Lead time
Quoted on each order. Because the parts are machined from bar rather than scheduled through a heading run, lead time is set by machining capacity and material availability. Ask for the current lead time with your RFQ.
Quality
Cyclone’s published certifications include AS9100D, AS9120B, ISO 9001:2015, API Spec Q1, API 20E and API 20F. See quality and certifications.
Documentation
Material test reports and certificates of conformance ship with the order. Additional inspection reports and documentation are quoted to the purchase order.
Questions before you quote
Is this a standard socket head cap screw?
No. The head is an 82-degree flat countersunk head with a hex socket, for flush mounting. A cylindrical socket head cap screw is a different sheet.
Does Cyclone stock these?
No. Every part is made to order from certified bar, which is why there is no minimum quantity and why the quote confirms sizes and lead time.
Can you quote a cancelled or superseded number?
Yes. Many MS sheets were reissued as NASM or SAE AS standards with the part numbers unchanged. Send the number on your drawing and the quote names the current document.