Value Collection 581955BR Hex Socket Cap Screw 1-3/8-12 Unf

Product Description

The VALUE COLLECTION 581955BR is a hex socket cap screw designed for high-strength fastening applications in mechanical, industrial, and fabrication environments. Manufactured from alloy steel with a black oxide finish, this fastener delivers corrosion resistance and a clean, low-reflectance appearance suited to precision assemblies. It carries a 1-3/8-12 UNF thread with a fully threaded shank measuring 4 inches under the head. The 1-inch hex drive accepts standard internal hex keys and drive tools. This screw meets ASME/ANSI B18.3 and ASTM A574 standards, making it appropriate for structural and load-bearing fastening tasks performed by machinists, millwrights, and maintenance mechanics.

This screw is used in heavy industrial machinery, hydraulic equipment, fixture building, and structural steel assemblies where a recessed hex drive is preferred over an external hex. The fine 12-TPI UNF thread provides greater thread engagement per inch compared to coarse thread equivalents, which improves holding strength in thinner materials and allows finer torque control. It is well suited to applications where vibration resistance and precise clamp load are required. Installation is typically performed by machinists or mechanical contractors working with steel components.

Key Features

• 1-3/8-12 UNF fine thread for increased holding strength and precise torque control
• Fully threaded shank at 4 inches under head for maximum thread engagement
• Alloy steel construction meets ASTM A574 high-strength fastener requirements
• Black oxide finish provides mild corrosion resistance and low-reflectance appearance
• 1-inch internal hex drive compatible with standard hex keys and socket drive tools
• Conforms to ASME/ANSI B18.3 dimensional standards

Compatibility

Designed as a standard ASME/ANSI B18.3 hex socket cap screw for use in any application requiring a 1-3/8-12 UNF fully threaded fastener in alloy steel.

Installation Notes

Installation is performed using a calibrated torque wrench with a 1-inch hex key or socket bit rated for the fastener grade. Power down and de-energize any equipment before disassembling or reassembling fastened assemblies. Threads and seating surfaces should be clean and free of debris before installation. Consult applicable engineering standards for torque specifications appropriate to the joint material and clamp load requirements.