Electro Hardware 1451M12F21-440 Hex Board Standoff 4-40

Product Description

The ELECTRO HARDWARE 1451M12F21-440 is a male-female hex circuit board standoff designed to create fixed spacing between PCBs, mounting panels, and enclosure surfaces in electronic assemblies. It features a 4-40 unified thread on both ends, with a hexagonal body that accepts a standard nut driver or wrench for secure installation. The body is steel with a zinc-plated finish that meets ASTM B633 Type 1 and QQ-S-633 standards for corrosion resistance. Overall length is 1.1875 inches with a 1/4-inch width across the hex flats. This standoff is installed by electronics technicians, control board assemblers, and field service technicians working on HVAC control boards, electrical panels, and industrial enclosures.

This standoff is suited for residential and commercial applications where circuit boards require precise mechanical separation from a chassis or secondary board. Typical use cases include HVAC control board mounting, variable frequency drive enclosures, relay panels, and similar low-voltage electronic assemblies. The male thread end drives into a tapped hole or mates with a female standoff below, while the female threaded end accepts a screw or a second standoff above, allowing stackable configurations. Grade 2 steel construction with zinc plating keeps weight low while providing adequate strength for board-mounting loads.

Key Features

• 4-40 male-female thread configuration allows stacking and single-tier circuit board mounting
• Hexagonal body shape accepts standard nut drivers and hex wrenches for torque control
• 1/4-inch width across flats for easy installation in tight enclosure layouts
• Zinc-plated steel finish meets ASTM B633 Type 1 and QQ-S-633 corrosion resistance standards
• Grade 2 steel construction provides reliable strength for circuit board mounting applications
• 1/4-inch thread depth on the female end and 3/16-inch thread length on the male end

Compatibility

Designed as an OEM-style replacement or new-installation standoff for circuit board assemblies using 4-40 unified thread fasteners in HVAC control panels, electrical enclosures, and industrial electronics requiring hex body standoffs.

Installation Notes

Installation is performed by electronics technicians or field service technicians working on control board assemblies. Disconnect and de-energize all circuits before handling circuit boards or installing standoffs. Use a properly sized nut driver matching the 1/4-inch hex flat to avoid rounding the body. Do not overtighten, as over-torquing 4-40 hardware in PCB mounting holes can crack board material or strip threads.