Holo-krome 72170 Hex Socket Cap Screw 3/8-16 Unc Alloy Steel

Product Description

The HOLO-KROME 72170 is a hex socket cap screw designed for high-strength fastening applications in mechanical assemblies, fixtures, and equipment. It features a 3/8-16 UNC thread with a 2.5-inch length under head and a 5/16-inch hex drive socket. The screw is partially threaded and manufactured from alloy steel with a black oxide coating, which provides moderate corrosion resistance and reduces light reflection in finished assemblies. This fastener meets ASME B18.3 and ASTM A574 standards, making it suitable for applications where dimensional accuracy and tensile strength are critical. Machinists, millwrights, and maintenance technicians are the typical end users.

This screw is used in industrial machinery, tooling fixtures, hydraulic components, and structural assemblies where a flush or recessed fastener head is required. The hex socket drive allows installation in confined spaces where a standard hex-head wrench cannot reach. The partial thread design provides a grip length that improves clamping force in thick-material applications. Typical installation environments include manufacturing facilities, field maintenance, and OEM equipment production.

Key Features

• 3/8-16 UNC thread for standard inch-series fastener compatibility
• 2.5-inch length under head with partial threading for improved clamping grip
• 5/16-inch hex socket drive for use with standard Allen keys or hex bit drivers
• Alloy steel construction meeting ASTM A574 high-strength cap screw requirements
• Black oxide finish for mild corrosion resistance and low-reflectance appearance
• Conforms to ASME B18.3 dimensional standards

Compatibility

Designed as a standard ASME B18.3 hex socket cap screw for use in any application requiring a 3/8-16 UNC partially threaded cap screw with a 2.5-inch length under head.

Installation Notes

Installation requires a 5/16-inch hex key or Allen-style bit driver. Ensure the mating threaded hole is clean and free of debris before driving the fastener. Do not over-torque; consult published torque tables for ASTM A574 alloy steel cap screws at the applicable thread size. Thread-locking compound may be applied where vibration resistance is required, per the equipment manufacturer's recommendations.