Electro Hardware P593M12F21-440 Female Hex Standoff 4-40

Product Description

The ELECTRO HARDWARE P593M12F21-440 is a female hex circuit board standoff designed to create precise spacing between PCBs, chassis panels, and mounting surfaces in electronic assemblies. Threaded 4-40 on the female end, this standoff accepts a matching male 4-40 fastener or screw, allowing stacked board configurations to be built and disassembled cleanly. The hex body measures 0.25 inches across flats, and the overall length is 1.5 inches. Manufactured from Grade 2 steel with a zinc-plated clear chromate finish, it meets ASTM B633 Type 1 and QQ-S-633 standards for corrosion resistance. Electronics assemblers, field technicians, and OEM service personnel commonly install these in control panels, HVAC circuit boards, and industrial enclosures.

This standoff is suited for residential and commercial electronic control board assemblies where a reliable, fixed-height spacer is required between PCB layers or between a board and a mounting surface. Typical applications include HVAC control board mounting, industrial control panel assemblies, and electronic enclosure builds where a 4-40 threaded hex standoff at 1.5 inches overall length is specified. The hex body shape allows installation and removal with standard open-end or box wrenches without marring the finish.

Key Features

• Female 4-40 thread accepts standard 4-40 male fasteners for secure board stacking
• 1.5-inch overall length provides consistent, fixed PCB spacing
• Hex body at 0.25 inches across flats allows wrench-driven installation and removal
• Grade 2 steel construction with zinc-plated clear chromate finish for corrosion resistance
• Meets ASTM B633 Type 1 and QQ-S-633 finish standards
• Length tolerance of -0.005 to 0.005 inches ensures dimensional consistency in close-tolerance assemblies

Compatibility

Designed as an OEM-style replacement or service standoff for electronic assemblies requiring a 4-40 female hex threaded spacer at 1.5 inches overall length in the inch measurement system.

Installation Notes

Installation is typically performed by electronics technicians or HVAC controls specialists. De-energize all circuits and discharge any capacitors before handling circuit boards or installing standoffs. Use a correctly sized open-end wrench or nut driver matched to the 0.25-inch hex flat to avoid rounding the body. Avoid over-torquing, as this can stress the board mounting holes or strip the 4-40 thread.