Electro Hardware S289M17F16E Round Circuit Board Spacer

Product Description

The ELECTRO HARDWARE S289M17F16E is a round, female unthreaded circuit board spacer designed to maintain precise standoff distances between PCBs and mounting surfaces or between stacked boards. Sized at 0.1875 inches overall length with a 0.116 inch inside diameter and 0.1875 inch outside diameter, this spacer accepts a number 4 screw and is molded from Nylon Grade 101. The uncoated finish and compliance with MIL-P-17091B make it appropriate for electronics assembly work in commercial, industrial, and military-adjacent applications. Electricians, electronics technicians, and PCB assembly professionals install these spacers during board mounting and rework.

This spacer is used wherever a compact, lightweight standoff is needed to isolate a circuit board from a chassis or adjacent board layer. Its small form factor suits densely populated PCB assemblies in control panels, HVAC control boards, and similar equipment. The female unthreaded body accepts a number 4 fastener, allowing for secure, vibration-resistant board mounting without threading the spacer body itself. Minimum order quantity is 100 units, making it suited for production assembly and service stock replenishment.

Key Features

• Nylon Grade 101 construction — lightweight, non-conductive, and chemically resistant
• Meets MIL-P-17091B fastener standard for dimensional and material consistency
• Female unthreaded design accepts number 4 screws without internal threading
• Tight dimensional tolerances: length tolerance of -0.005 to 0.005 inches, ID tolerance of 0.000 to 0.010 inches
• Uncoated bright finish — no secondary coating to affect dielectric properties or board clearance
• Round body shape for symmetrical load distribution on PCB mounting holes

Compatibility

Designed as an OEM-style replacement or production-run spacer for circuit board assemblies requiring a number 4 screw, female unthreaded round standoff with a 3/16 inch overall length and 3/16 inch outside diameter.

Installation Notes

Electronics technicians and PCB assembly personnel install these spacers during board mounting or rework procedures. Power down and de-energize all circuits before handling or repositioning any circuit board assembly. Use appropriate ESD precautions when working near populated boards. Do not overtighten the mating number 4 fastener, as nylon spacers can crack or deform under excessive clamping load.