Armor Coat UST235749 Hex Head Cap Screw 1/4-28 X 4 in Grade 8

Product Description

The ARMOR COAT UST235749 is a Grade 8 steel hex head cap screw designed for high-strength fastening applications requiring a fine-thread profile and partial threading. Sized at 1/4-28 UNF with a 4-inch length under the head, this fastener meets ASME B18.2.1 and SAE J429 standards, confirming it has been produced to the mechanical and dimensional requirements expected in demanding industrial and trade environments. The partial threading allows the unthreaded shank to bear shear loads, making it well suited for bolted joints where clamp load distribution and shear resistance are both critical. It weighs approximately 0.01 pounds per piece.

This cap screw is used across a wide range of trade applications where a fine-thread, high-strength hex fastener is required. Typical use cases include mechanical assemblies, HVAC equipment mounting, electrical enclosure hardware, and general industrial maintenance where UNF thread engagement and Grade 8 strength are specified. The inch-system thread sizing and standard hex drive make it compatible with common hand and power tools found on any service truck or shop floor. It is sold individually with a minimum order quantity of 10 pieces.

Key Features

• Grade 8 steel construction for high tensile and yield strength in demanding fastening applications
• 1/4-28 UNF fine thread provides tighter thread engagement and greater resistance to loosening under vibration
• Partial threading allows the unthreaded shank to handle shear loads in bolted assemblies
• 4-inch length under head accommodates thicker material stacks or deeper through-bolt installations
• Meets ASME B18.2.1 and SAE J429 standards for dimensional accuracy and mechanical properties
• Standard hex head drive is compatible with 7/16-inch wrenches and sockets

Compatibility

Designed as an OEM-style replacement or service fastener for any application specifying a 1/4-28 UNF Grade 8 hex head cap screw with a 4-inch length under head per inch measurement standards.

Installation Notes

Installation should be performed by a qualified mechanic or trade professional familiar with fastener torque requirements for Grade 8 hardware at this thread size. Always verify thread engagement depth and mating material compatibility before installation. De-energize or shut down any equipment being serviced before removing or replacing structural fasteners. Do not substitute a lower-grade fastener in any joint originally specified for Grade 8 hardware.