Electro Hardware MS1031M01F21D Circuit Board Spacer M3

Product Description

The ELECTRO HARDWARE MS1031M01F21D is a round, female unthreaded circuit board spacer designed for M3 screw applications in printed circuit board assemblies. Made from brass with a zinc-plated finish meeting ASTM B633 and QQ-B-626 Comp 22 Type 1 standards, this spacer provides reliable standoff and electrical isolation between board layers or mounting surfaces. It measures 16 mm overall length with a 6 mm outside diameter and an inside diameter ranging from 3.2 to 3.6 mm. The metric form factor and tight length tolerance of -0.13 to 0.13 mm make it suitable for precision PCB stacking applications. Electricians, electronics technicians, and panel builders use this type of hardware during board assembly and enclosure builds.

This spacer is used wherever M3 fasteners are employed to mount or stack circuit boards in control panels, HVAC control assemblies, electrical enclosures, and similar equipment. Its brass construction with zinc plating offers corrosion resistance in moderate-duty environments. The female unthreaded bore accepts M3 fasteners for pass-through or standoff mounting configurations. It is sold individually with a minimum order quantity of 10 units, making it appropriate for small assembly runs or service stock replenishment.

Key Features

• Brass body with zinc-plated finish per ASTM B633 and QQ-B-626 Comp 22 Type 1
• Female unthreaded bore sized for M3 screw applications
• 16 mm overall length with tight tolerance of -0.13 to 0.13 mm for consistent stack height
• 6 mm outside diameter with round body shape for standard PCB standoff use
• Inside diameter range of 3.2 to 3.6 mm accommodates M3 fastener clearance
• Metric measurement system for compatibility with metric hardware assemblies

Compatibility

Designed as an OEM-style replacement or service spacer for circuit board assemblies using M3 metric fasteners and requiring a 16 mm standoff height with a 6 mm round body profile.

Installation Notes

Installation is typically performed by electronics technicians or electricians during board assembly or control panel servicing. De-energize all equipment and discharge any capacitors before working inside control enclosures or on mounted circuit boards. Use appropriately sized M3 fasteners and avoid overtightening, which can crack the board or deform the spacer. Follow applicable NEC or equipment manufacturer guidelines for control panel assembly clearances.