Electro Hardware 1305M03F21440 Hex Standoff 4-40

Product Description

The ELECTRO HARDWARE 1305M03F21440 is a male-female hex circuit board standoff designed to create precise spacing between PCBs and mounting surfaces in electronic assemblies. The standoff features a 4-40 unified thread on both the male and female ends, an overall body length of 0.25 inches, and a hex body shape measuring 0.1875 inches (3/16 inches) across the flats. It is machined from brass and finished with a zinc plating that meets ASTM B633 Type 1 and QQ-B-626 Comp 22 standards. Electronics assembly technicians, control board fabricators, and field service technicians working on HVAC, electrical, and industrial control panels install these standoffs during board mounting and chassis assembly.

This standoff is used wherever a circuit board must be raised and secured at a fixed, consistent height above a mounting surface. It suits residential and commercial control board assemblies, HVAC equipment PCBs, and general electronic enclosures. The male end threads into the mounting surface or a previously installed standoff, while the female end accepts a machine screw to capture the board. The compact 1/4-inch body length makes it well suited for tight PCB stack-ups and dense control panel layouts.

Key Features

• 4-40 unified thread on both male and female ends for secure, positive engagement
• Hex body shape at 0.1875 inches across flats allows standard hex driver installation
• Brass construction with zinc plating resists corrosion in enclosure environments
• Meets ASTM B633 Type 1 and QQ-B-626 Comp 22 finish and material standards
• Length tolerance of -0.005 to +0.005 inches ensures consistent board standoff height
• Overall body and thread length of 0.25 inches fits compact PCB mounting applications

Compatibility

Designed as an OEM-style and general-use replacement standoff for circuit board mounting applications requiring a 4-40 thread size and a 3/16-inch hex body width in brass zinc-plated construction.

Installation Notes

Installation is performed by electronics technicians or field service professionals. De-energize all equipment and discharge any capacitors before handling circuit boards or standoffs. Use a properly sized hex driver or nut driver matching the 3/16-inch across-flats dimension to avoid rounding the hex body. Do not overtighten, as brass standoffs can be damaged by excessive torque; snug to finger-tight plus a quarter turn with a hand tool is the standard practice for this fastener class.