Electro Hardware MMF1321M03F21M3 Hex Standoff M3x0.5

Product Description

The ELECTRO HARDWARE MMF1321M03F21M3 is a male-female hex circuit board standoff designed to mount and space PCBs within electronic enclosures and control panels. Machined from brass with a zinc-plated finish, it meets ASTM B633 Type 1 and QQ-B-626 Comp 22 standards for finish quality and corrosion resistance. The standoff features an M3 x 0.5 thread on both ends - a male thread on one end and a female threaded bore on the other - allowing boards to stack or mount securely. The hexagonal body measures 4.5 mm across flats, allowing standard hex drivers or wrenches to seat and torque the fastener without slipping. Overall length is 19.76 mm with a body length of 15.00 mm.

This standoff is used in residential and commercial electronic control assemblies, HVAC control boards, electrical enclosures, and industrial PCB mounting applications. It is a metric-threaded component suited for any panel or board assembly that specifies M3 x 0.5 hardware. Electricians, control panel builders, and electronics technicians install these during board mounting and replacement work where proper PCB spacing and rigid mechanical support are required.

Key Features

• Male-female configuration allows secure PCB stacking and spacing
• M3 x 0.5 metric thread on both ends for precise engagement
• Hexagonal body at 4.5 mm across flats for tool-driven installation
• Zinc-plated brass construction for corrosion resistance in enclosure environments
• Compliant with ASTM B633 Type 1 and QQ-B-626 Comp 22 finish standards
• Length tolerance held to -0.150 to 0.150 mm for consistent board spacing

Compatibility

Designed as an OEM-style replacement or new-installation component for any PCB assembly, control board, or electronic enclosure specifying M3 x 0.5 metric hex standoffs.

Installation Notes

Install and remove with a hex driver or open-end wrench sized to 4.5 mm across flats. De-energize all circuits and discharge any capacitors before working on control boards or panel assemblies. Do not overtighten - brass fasteners are susceptible to thread damage if over-torqued against harder mounting surfaces. Follow applicable NEC guidelines when installing or servicing electronic control panels.