Electro Hardware MMF1853M03F21M3 Hex Standoff M3x0.5

Product Description

The ELECTRO HARDWARE MMF1853M03F21M3 is a male-female hex circuit board standoff designed to create precise, repeatable spacing between stacked PCBs or between a board and a mounting surface. One end threads into an existing female hole or standoff; the other end presents a male thread that accepts the next board or component. The hex body allows wrench engagement for secure, torque-controlled installation. It is machined from brass with a zinc-plated finish that meets ASTM B633 Type 1 and QQ-B-626 Comp 22 standards. Overall length is 35.76 mm (approximately 1.41 inches), body length is 31.00 mm, thread size is M3 x 0.5, and width across the hex flats is 6.00 mm.

This standoff is used in electronics assembly, control board mounting, and enclosure builds where a rigid, electrically isolated or mechanically secure board stack is required. Typical applications include industrial control panels, HVAC circuit board assemblies, power supply enclosures, and general PCB chassis mounting. It is installed by electronics assemblers, panel builders, and field technicians performing control board service or replacement. The metric M3 x 0.5 thread makes it compatible with metric-threaded PCB mounting holes and hardware commonly found in European-standard and metric-based control assemblies.

Key Features

• Male-female configuration allows daisy-chaining of multiple board layers in a single standoff stack
• Hex body shape (6.00 mm across flats) accepts standard nut drivers and wrenches for positive torque control
• Brass construction with zinc-plated finish provides corrosion resistance per ASTM B633 Type 1 and QQ-B-626 Comp 22
• M3 x 0.5 thread on both ends with a thread length of 4.76 mm and thread depth of 6.40 mm
• Overall length of 35.76 mm with a tight length tolerance of -0.150 to 0.150 mm for consistent board spacing

Compatibility

Designed as an OEM-style metric standoff for PCB and control board assemblies using M3 x 0.5 threaded mounting holes.

Installation Notes

Installation is performed by electronics assemblers or licensed electricians working on control panel builds. Power down and de-energize the assembly before installing or removing standoffs in any live panel or control board application. Use a properly sized nut driver or hex wrench matched to the 6.00 mm flat width to avoid rounding the hex body. Do not over-torque; brass hardware is subject to thread stripping if excessive force is applied.