Electro Hardware MMF1303M03F21M3 Hex Board Standoff M3

Product Description

The ELECTRO HARDWARE MMF1303M03F21M3 is a male-female hex circuit board standoff designed to create precise spacing between stacked PCBs or between a circuit board and a mounting surface. Threaded M3 x 0.5 on both ends, this standoff accepts a machine screw on the male end and a mating standoff or screw on the female end. The hex body measures 4.5 mm across flats for positive wrench engagement. Constructed from brass with a zinc-plated finish, it meets ASTM B633 Type 1 and QQ-B-626 Comp 22 standards. Overall length is 10.76 mm with a body length of 6.00 mm. Installed by electronics technicians, PCB assemblers, and field service engineers during board-level assembly and panel builds.

This standoff is used in residential and commercial electronic control assemblies, industrial enclosures, HVAC control boards, and any application requiring a rigid, threaded separation between printed circuit boards or mounting panels. The metric M3 thread size makes it compatible with standard metric fastener systems commonly found in equipment manufactured to metric specifications. Minimum order quantity is 10 pieces.

Key Features

• Male-female thread configuration allows stacking of multiple boards or mounting to a panel with a single fastener pass-through
• M3 x 0.5 thread size on both male and female ends
• Hex body at 4.5 mm across flats allows standard hex driver or wrench installation
• Brass construction with zinc-plated finish for corrosion resistance per ASTM B633 Type 1 and QQ-B-626 Comp 22
• Overall length of 10.76 mm with a 4.76 mm thread length on the male end and 6.40 mm thread depth on the female end
• Length tolerance of -0.150 to +0.150 mm for consistent board spacing

Compatibility

Designed as a metric M3 x 0.5 threaded standoff suitable for use in any PCB assembly or electronic enclosure application requiring a hex male-female spacer at this thread size and overall length.

Installation Notes

Installation is typically performed by electronics technicians or control board assemblers using a standard hex driver or wrench sized for 4.5 mm across flats. Power down and de-energize all circuits before installing or removing standoffs from live control boards. Avoid overtightening, as brass threads can gall or strip when excessive torque is applied. Follow applicable assembly standards and enclosure manufacturer guidelines for fastener torque and PCB support spacing.