Value Collection -33721-1 Hex Socket Cap Screw 1-1/4-7 Unc

Product Description

The VALUE COLLECTION -33721-1 is a hex socket cap screw designed for high-strength fastening applications requiring a recessed drive interface. Sized at 1-1/4-7 UNC thread with a 3.5-inch length under head, this fastener is fully threaded and driven with a 7/8-inch hex key. Constructed from alloy steel with a black oxide finish, it meets ASME/ANSI B18.3 and ASTM A574 standards. Machinists, maintenance technicians, and mechanical contractors install this type of fastener where a flush or countersunk head profile and high clamp load are required.

This screw is suited for heavy-duty mechanical assemblies, industrial equipment, and structural connections where a standard hex head is not practical. The large 1-1/4-7 UNC thread diameter makes it appropriate for thick-section steel, cast iron, or heavy plate applications. It is commonly installed in manufacturing, machine building, and industrial maintenance environments where ASME B18.3 socket cap screws are specified.

Key Features

• 1-1/4-7 UNC thread size for high-load fastening in heavy-section material
• 3.5-inch length under head, fully threaded along the entire shank
• 7/8-inch hex drive for positive torque transfer with a standard hex key or bit socket
• Alloy steel construction meets ASTM A574 for high-strength socket cap screw requirements
• Black oxide finish provides mild corrosion resistance and reduces light reflection
• Complies with ASME/ANSI B18.3 dimensional and mechanical standards

Compatibility

Designed as an OEM-style or maintenance replacement hex socket cap screw for industrial machinery, structural assemblies, and equipment requiring ASME/ANSI B18.3 compliant 1-1/4-7 UNC fully threaded fasteners.

Installation Notes

Installation is performed by machinists or mechanical maintenance technicians using a 7/8-inch hex key or bit socket and appropriate torque wrench. De-energize and lock out all equipment before replacing fasteners in powered machinery per OSHA lockout/tagout procedures. Verify thread engagement depth and mating thread condition before torquing. Do not substitute black oxide fasteners in outdoor or wet environments without additional corrosion protection.