Electro Hardware MMF1329M03F21M3 Hex Standoff M3

Product Description

The ELECTRO HARDWARE MMF1329M03F21M3 is a male-female hex circuit board standoff designed to create precise spacing between PCBs and mounting surfaces in electronic assemblies. The standoff features an M3 x 0.5 thread on both ends - a male thread on one side and a female threaded bore on the other - allowing boards to be stacked or secured in a fixed, repeatable position. The hex body measures 4.5 mm across flats for wrench engagement. Overall length is 23.76 mm, with a body length of 19.00 mm and a thread depth of 6.40 mm on the female end. Constructed from brass with a zinc-plated finish conforming to ASTM B633 Type 1 and QQ-B-626 Comp 22, this standoff delivers corrosion resistance suitable for long-term installation inside control panels and enclosures.

This standoff is used in electronic and electrical control assemblies where circuit boards must be mounted at a fixed height above a panel or stacked in a multi-board configuration. Typical applications include HVAC control boards, industrial relay panels, variable-frequency drives, and general PCB enclosures. The metric M3 x 0.5 thread sizing is common in commercial and light industrial electronic equipment. Installers working with metric fastener systems will find this standoff a direct fit for standard M3 threaded mounting points on circuit boards and chassis.

Key Features

• Male-female configuration allows board stacking and panel mounting in a single fastener
• Hex body at 4.5 mm across flats accepts standard metric wrenches and nut drivers for secure torquing
• Brass base material with zinc-plated finish provides corrosion resistance in enclosed environments
• Meets ASTM B633 Type 1 and QQ-B-626 Comp 22 finish standards
• Overall length of 23.76 mm with a length tolerance of -0.150 to 0.150 mm for consistent board spacing
• M3 x 0.5 metric thread sizing compatible with standard PCB mounting hardware

Compatibility

Designed as a standard M3 x 0.5 male-female hex standoff suitable for circuit board mounting and stacking applications in electronic assemblies using metric fastener systems.

Installation Notes

Power down and de-energize the equipment completely before servicing any circuit board mounting hardware. Use an appropriate metric nut driver or open-end wrench sized for 4.5 mm across flats to install and tighten the standoff without over-stressing the PCB. Minimum order quantity for this part is 10 units - confirm required quantity before ordering. Follow applicable electrical codes and manufacturer assembly documentation when mounting control boards in panel enclosures.