Electro Hardware MS1021M01F21F Round Circuit Board Spacer M4

Product Description

The ELECTRO HARDWARE MS1021M01F21F is a round, female unthreaded circuit board spacer machined from brass and finished with a zinc plating. It is designed to create a fixed standoff distance between a printed circuit board and a mounting surface or secondary board. The spacer accepts an M4 screw, measures 11 mm in overall length, and features an outside diameter of 6 mm with an inside diameter ranging from 4.2 mm to 4.8 mm. Its brass construction combined with a zinc finish provides corrosion resistance in light-duty indoor electronic assemblies. The part conforms to ASTM B633 and QQ-B-626 Comp 22 Type 1 standards, making it suitable for applications that require traceable fastener specifications.

This spacer is used wherever a circuit board must be held at a precise standoff distance from an adjacent surface. Typical applications include control board mounting in HVAC equipment, electrical enclosures, industrial automation panels, and similar assemblies where an M4 metric fastener pattern is specified. The female unthreaded bore allows a screw or standoff to pass through or seat against the spacer body. It is well-suited to residential and light commercial equipment repairs or original equipment assembly work where metric hardware is standard.

Key Features

• Female unthreaded bore sized for M4 screw, inside diameter 4.2 mm to 4.8 mm
• 11 mm overall length with a tight length tolerance of -0.13 mm to 0.13 mm
• 6 mm outside diameter, round body profile
• Brass body with zinc-plated finish per ASTM B633 and QQ-B-626 Comp 22 Type 1
• Metric measurement system for compatibility with M4 fastener assemblies
• UNSPSC Code 31161816 for procurement classification

Compatibility

Designed as an OEM-style replacement or assembly component for circuit board mounting applications that use M4 metric screw patterns and require a 6 mm OD round spacer with an 11 mm standoff height.

Installation Notes

Installation is performed by electronics technicians or licensed electricians during control board mounting or panel assembly work. De-energize all circuits and discharge any stored capacitor energy before working inside an electrical enclosure or control panel. Use appropriately sized metric hand tools; avoid over-torquing the mating M4 fastener to prevent deforming the unthreaded brass bore. Follow applicable NEC guidelines and equipment manufacturer instructions for control board mounting clearances.