Value Collection 36881 Flat Socket Cap Screw 1/2-20 X 1-1/2 in

Product Description

The VALUE COLLECTION 36881 is a flat socket cap screw designed for applications requiring a flush or countersunk fastener profile. It features an 82-degree flat head driven by a 5/16-inch hex socket. The screw is fully threaded with a 1/2-20 UNF thread pattern and measures 1-1/2 inches in overall length. Constructed from alloy steel with a black oxide finish, it provides moderate corrosion resistance and a low-reflectance appearance suited to industrial and mechanical assemblies. Installation requires a standard hex key or Allen driver. This fastener is used by machinists, millwrights, and maintenance technicians across manufacturing, tooling, and structural assembly work.

This screw is appropriate for both light and heavy mechanical assemblies where a countersunk fastener is needed to sit flush with or below the mating surface. The 1/2-20 UNF fine thread offers greater thread engagement and improved resistance to loosening under vibration compared to coarse thread equivalents. It is commonly used in jigs, fixtures, machine components, and equipment housings. Each package contains 10 screws with a minimum order quantity of 1 package.

Key Features

• 82-degree flat head profile for flush or countersunk installations
• 5/16-inch hex socket drive for reliable torque transmission
• 1/2-20 UNF fully threaded shank for maximum thread engagement
• Alloy steel construction for high tensile strength
• Black oxide finish provides mild corrosion resistance and reduces light reflection
• Meets ASME/ANSI B18.3 and ASTM F835 fastener standards

Compatibility

Designed as a standard UNF flat socket cap screw conforming to ASME/ANSI B18.3 and ASTM F835, suitable for use in any tapped hole or countersunk application requiring a 1/2-20 fine thread fastener.

Installation Notes

Installation is performed with a 5/16-inch hex key or Allen wrench. Ensure the mating surface is properly countersunk to 82 degrees before installing to achieve a flush seating condition. Follow applicable torque guidelines for 1/2-20 alloy steel fasteners per the relevant engineering or maintenance specification. Black oxide finish offers limited corrosion protection and should not be relied upon as the sole corrosion barrier in wet or chemical environments.