Electro Hardware MS1039M01F21D Circuit Board Spacer M3

Product Description

The ELECTRO HARDWARE MS1039M01F21D is a round, female unthreaded circuit board spacer designed to create precise standoff clearance between a PCB and a mounting surface or adjacent board. Constructed from brass with a zinc-plated finish meeting ASTM B633 and QQ-B-626 Comp 22 Type 1 standards, this spacer accepts an M3 screw and measures 20 mm in overall length. The inside diameter ranges from 3.2 to 3.6 mm, and the outside diameter is 6 mm. Electronics assemblers, electrical technicians, and PCB repair professionals use this spacer in both production and field-service applications where consistent board-to-board or board-to-chassis spacing is required.

This spacer is suited for metric-fastener assemblies in residential and commercial electronics, control panels, and industrial PCB mounting configurations. The M3 thread compatibility makes it a standard fit in a wide range of low-voltage control board assemblies, enclosure-mounted electronics, and HVAC or appliance control modules that rely on metric hardware. It installs where dimensional consistency and corrosion resistance are required in the standoff column.

Key Features

• Brass body with zinc-plated finish for corrosion resistance per ASTM B633 and QQ-B-626 Comp 22 Type 1
• Female unthreaded design accepts M3 screws for straightforward PCB standoff assembly
• 20 mm overall length with a tight length tolerance of -0.13 to 0.13 mm for consistent stack height
• Inside diameter of 3.2 to 3.6 mm with an inside diameter tolerance of 0.000 to 0.270 mm
• 6 mm outside diameter in a compact round body profile
• Metric system of measurement for compatibility with M3 fastener ecosystems

Compatibility

Designed as an OEM-style replacement or new-build component for metric PCB standoff applications requiring an M3 female unthreaded brass spacer with a 20 mm overall length.

Installation Notes

Installation is performed by electronics technicians or electricians working on control board assemblies. Power down and de-energize all circuits before servicing any PCB or control enclosure. Use appropriate M3 fasteners and a calibrated torque tool to avoid over-stressing the unthreaded bore. Follow applicable NEC guidelines and equipment manufacturer instructions when mounting control boards in electrical enclosures.