Value Collection 581589P Hex Head Cap Screw 1/2-20

Product Description

The VALUE COLLECTION 581589P is a hex head cap screw designed for high-strength fastening in demanding mechanical and structural applications. It features a 1/2-20 UNF thread pattern on a 3-3/4 inch overall length shank with partial threading, leaving a smooth grip section toward the head. The fastener is manufactured from alloy steel and finished with a black oxide coating that provides moderate corrosion resistance and reduces light reflection on exposed hardware. Installation requires a standard hex wrench or socket. Electricians, millwrights, and general contractors commonly use fasteners of this type where fine-thread engagement and controlled clamp load are required.

This cap screw is suited for bolted joint assemblies in industrial equipment, machinery mounts, fixtures, and structural connections where a fine-thread UNF pattern is specified. The partial thread design allows the unthreaded shank to act as a shoulder or locating surface within a clearance hole, improving alignment and shear resistance in the joint. It is appropriate for both shop fabrication and field installation work.

Key Features

• 1/2-20 UNF fine-thread pattern for precise thread engagement and vibration resistance
• 3-3/4 inch overall length with partial threading for shoulder-style load distribution
• Alloy steel construction for high tensile strength and durability under mechanical load
• Black oxide finish for moderate corrosion resistance and low-glare appearance
• Hex head drive compatible with standard sockets and wrenches

Compatibility

Designed as a standard UNF hex head cap screw for use in any 1/2-20 tapped hole or hex nut application requiring a 3-3/4 inch partially threaded alloy steel fastener.

Installation Notes

Installation should be performed by a qualified mechanic, millwright, or tradesperson familiar with bolted joint assembly practices. Always verify that the mating thread is 1/2-20 UNF before driving the fastener. Do not substitute an SAE or metric nut for the specified UNF nut, as thread mismatch will damage both components. Follow applicable torque specifications from the equipment manufacturer or relevant industry standards for the fastener grade in use.