Electro Hardware MS1007M01F21F Round Circuit Board Spacer M4

Product Description

The ELECTRO HARDWARE MS1007M01F21F is a round, female unthreaded circuit board spacer designed for M4 screw applications in printed circuit board assemblies. Constructed from brass with a zinc-plated finish meeting ASTM B633 and QQ-B-626 Comp 22 Type 1 standards, this spacer provides reliable standoff support and electrical isolation between board layers or between a board and a mounting surface. The overall length is 4 mm, the outside diameter is 6 mm, and the inside diameter ranges from 4.2 to 4.8 mm. It is sized and toleranced for consistent, repeatable fitment in metric-spec assemblies.

This spacer is used in residential and commercial electronics assembly, control board manufacturing, and field replacement of circuit board hardware in HVAC controls, electrical enclosures, and industrial equipment. It is installed by electronics technicians, electrical contractors, and OEM assembly technicians wherever a secure, corrosion-resistant metric standoff is required between a PCB and a chassis or secondary board layer.

Key Features

• Brass body with zinc-plated finish for corrosion resistance, compliant with ASTM B633 and QQ-B-626 Comp 22 Type 1
• Female unthreaded design accepts M4 fasteners for secure board standoff mounting
• 4 mm overall length with tight length tolerance of -0.13 to 0.13 mm for consistent stack height
• Inside diameter tolerance of 0.000 to 0.270 mm ensures reliable M4 screw fitment
• Round body shape with 6 mm outside diameter for standard PCB mounting hole patterns
• Metric measurement system for compatibility with international fastener standards

Compatibility

Designed as an OEM-style replacement or service spacer for metric M4 circuit board standoff applications in control boards, electrical enclosures, and PCB assemblies requiring a 4 mm brass spacer with zinc-plated finish.

Installation Notes

This spacer is installed by electronics technicians or licensed electricians working on control board assemblies or enclosures. Power down and de-energize all circuits before removing or installing circuit board hardware. Use appropriately sized M4 fasteners and avoid overtightening, which can crack the board substrate or deform the spacer. Follow applicable NEC guidelines when servicing energized electrical enclosures.