Value Collection -48409-9 Flat Socket Cap Screw 7/8-9 X 4 in

Product Description

The VALUE COLLECTION -48409-9 is a flat socket cap screw designed for applications requiring a flush or countersunk fastener with high tensile strength. The 82-degree flat head seats cleanly into a countersunk hole, eliminating protrusion above the mating surface. Drive engagement is through a 9/16-inch hex socket. The fastener is manufactured from alloy steel and finished in black oxide for mild corrosion resistance and reduced light reflection. At 7/8-9 UNC thread with a 4-inch overall length and partial threading, this screw is suited for heavy-duty mechanical assemblies where a flush profile is required. Installation is performed by qualified machinists, millwrights, or maintenance professionals.

This screw is used in structural and mechanical assemblies where the fastener head must sit flush with or below the work surface. The 7/8-9 UNC coarse thread makes it well suited for steel plate, machine frames, and fabricated components where thread engagement depth is available. Partial threading provides full shank bearing load capacity through the joint. The black oxide finish is appropriate for interior or low-moisture industrial environments. Sold in a package quantity of five per order.

Key Features

• 82-degree flat head profile for flush countersunk installation
• 9/16-inch hex socket drive for high-torque engagement
• 7/8-9 UNC coarse thread for compatibility with standard tapped steel components
• Partially threaded shank supports shear load across the joint interface
• Alloy steel construction meets ASME/ANSI B18.3 and ASTM F835 standards
• Black oxide finish provides mild corrosion resistance in low-moisture environments

Compatibility

Designed as an OEM-style replacement or standard-fitment flat socket cap screw for industrial and mechanical assemblies requiring a 7/8-9 UNC countersunk fastener per ASME/ANSI B18.3 and ASTM F835 specifications.

Installation Notes

Installation should be performed by a qualified machinist or maintenance technician using a calibrated 9/16-inch hex key or socket driver. Ensure the countersunk hole angle matches the 82-degree flat head geometry before seating the fastener. De-energize and lock out any machinery before fastener replacement or assembly work per applicable safety procedures. Do not exceed the rated drive engagement depth to avoid socket or fastener damage.