- Head Type: Flat countersunk head with recessed hex socket drive
- Head Angle: 82° (ASME B18.3 inch series) or 90° (ISO 10642/DIN 7991 metric series)
- Material Options: Heat-treated alloy steel, 18-8 (304) stainless steel, 316 stainless steel, aluminum alloy
- Property Class / Grade: 12.9 (metric), ASTM F835 (inch), Grade 8.8 available on request
- Thread Range: #2-56 to 3/4″-10 (inch), M3 to M20 (metric)
- Socket Size: Inch: 0.050″ (#2) to 3/8″ (3/4″); Metric: 2mm to 10mm
- Finishes: Black oxide, zinc (clear/yellow chromate), passivated stainless, or plain finish
- Tensile Strength: 180,000 psi (inch series) or 1220 MPa (metric class 12.9)
- Thread Standards: UNC, UNF, and ISO coarse/fine pitch

- Description
- Features
- Specifications
FLAT HEAD SOCKET CAP SCREWS
Flat head socket cap screws also known as countersunk socket screws are engineered for applications requiring a completely flush surface and uncompromising performance. Their conical head seats fully into a countersunk feature, creating a smooth, snag-free finish ideal for equipment housings, machinery assemblies, electronics, transportation interiors, architectural components, and any application where head protrusion is unacceptable.
Designed with a recessed hex socket, these fasteners offer superior torque transfer, exceptional driver control, and reduced cam-out compared to slotted or Phillips countersunk screws. The geometry of the head, drive, bearing surface, fillet radius, and concentricity follows strict dimensional standards to ensure repeatability and consistent clamp force in OEM environments.
ENGINEERING & PERFORMANCE CHARACTERISTICS
- Available in coarse, fine, and specialty thread pitches (UNC, UNF, ISO).
- Manufactured to high tensile strength and torque-to-tension performance expectations.
- Socket depth and head concentricity controlled for repeatable torque values.
- Chamfered or flat points for clean installation.
COMMON APPLICATIONS
- Industrial machinery and automation
- Aerospace and automotive interiors
- Electronics, computing, and instrumentation
- Architectural fittings and visible surfaces
- Marine and chemical environments with appropriate alloys
WHY G-FAST DISTRIBUTION
Our engineering-focused approach ensures each fastener meets strict quality and performance standards. Whether standard or custom-manufactured, our flat head socket cap screws deliver the precision, strength, and reliability required for modern industrial design.
- True flush installation with no protruding head profile.
- Internal hex socket drive for maximum torque engagement and reduced cam-out.
- Precision-machined geometry for consistent seating and load distribution.
- Inch (82°) and metric (90°) head angle options for correct fit.
- Ideal for thin materials, visible surfaces, and pre-finished components.
- Suitable for automated or robotic fastening.
AVAILABLE MATERIALS
G-Fast Distribution supplies flat head socket cap screws in a broad range of performance materials:
Carbon & Alloy Steels
- High-strength heat-treated alloy steel
- Black oxide, zinc, phosphate, or plain finish
Stainless Steels
- 300 Series Stainless (18-8 / 304, 316)
- 410 Bright Hardened Stainless for improved strength and torque resistance
Advanced & Exotic Materials
- Titanium – lightweight, corrosion-resistant, non-magnetic
- Monel – superior resistance to saltwater and chemicals
- Hastelloy – engineered for extreme corrosion and high temperatures
- Additional specialty grades available upon request
INCH & METRIC AVAILABILITY
- Inch: #2-56 through 3/4-10
- Metric: M3 through M20
- Custom lengths, modified geometries, and made-to-print fasteners supported through Fasteneering™