Value Collection MSC-67480244 Heavy Hex Jam Nut 7/8-9 Unc

Product Description

The VALUE COLLECTION MSC-67480244 is a heavy hex jam nut designed for secure fastening in threaded assemblies where a low-profile locking nut is required. Machined from steel with a 7/8-9 UNC thread specification and a 2B class of fit, this nut delivers reliable thread engagement in standard unified coarse-thread applications. At 1-7/16 inches across flats and 31/64 inches high, the heavy hex profile provides additional bearing surface compared to standard hex jam nuts, making it suitable for high-load or vibration-prone installations. The uncoated finish is appropriate for use in dry or protected environments. Plumbers, pipefitters, millwrights, and general mechanical contractors will find this nut applicable across a wide range of structural and equipment-mounting tasks.

This heavy hex jam nut is used wherever a thin locking nut is needed to secure a primary nut or to fasten components in tight axial clearance situations. Typical applications include mechanical equipment mounting, structural assemblies, piping supports, and industrial machinery where a 7/8-9 UNC threaded fastener is specified. The heavy hex body is commonly called for in ASME and similar structural fastening standards. Right-hand thread direction follows standard convention for most mechanical and plumbing applications.

Key Features

• 7/8-9 UNC thread specification with right-hand thread direction
• 2B class of fit for standard unified coarse-thread engagement
• Heavy hex profile — 1-7/16 inches across flats for increased bearing surface
• Low-profile jam nut height of 31/64 inches for tight-clearance locking applications
• Steel construction, uncoated finish
• Does not meet military specifications

Compatibility

Designed as an OEM-style replacement or maintenance fastener for any assembly using a 7/8-9 UNC heavy hex jam nut with a 2B thread fit class.

Installation Notes

Installation is performed by millwrights, pipefitters, or general mechanics using a standard open-end or box wrench sized for 1-7/16-inch hex. Always de-energize or depressurize the assembly before servicing fasteners on live systems. Torque the primary nut to the assembly specification first, then back the jam nut against it to lock the joint. Do not use this uncoated nut in continuously wet or corrosive environments without additional protective measures.