Electro Hardware S577-M10-F21-E Circuit Board Spacer

Product Description

The ELECTRO HARDWARE S577-M10-F21-E is a round, female unthreaded circuit board spacer designed to maintain precise standoff distances between printed circuit boards and mounting surfaces or between stacked boards. Manufactured from Grade 2 steel with a zinc-plated finish conforming to ASTM B633 and QQ-S-633 Type 1, it delivers reliable corrosion resistance in electronics enclosure environments. The spacer measures 1.25 inches overall length, with a 0.116 inches inside diameter and a 0.25 inches outside diameter. It is sized for No. 4 screw installations. Licensed electricians, control board technicians, and electronics assembly professionals use this hardware during control panel builds, PCB mounting, and board replacement service work.

This spacer is suited for residential and commercial electronic control assemblies, HVAC control boards, and general PCB mounting applications where a standardized steel standoff is required. Its female unthreaded body accepts a No. 4 screw and is specified under inch-measurement standards. The zinc-plated steel construction makes it appropriate for indoor enclosures and panel environments where light corrosion resistance is needed. It ships individually and can be ordered in single-unit quantities.

Key Features

• Female unthreaded body sized for No. 4 screws
• 1.25 inches overall length with tight length tolerance of -0.005 to 0.005 inches
• 0.116 inches inside diameter with tolerance of 0.000 to 0.010 inches
• 0.25 inches outside diameter, round body profile
• Grade 2 steel construction with zinc-plated finish per ASTM B633 and QQ-S-633 Type 1

Compatibility

Designed as a standard-dimension replacement or new-installation circuit board spacer for No. 4 screw PCB mounting applications following inch-measurement specifications.

Installation Notes

Installation is performed by qualified electronics technicians or licensed electricians during control board mounting or replacement. De-energize all circuits and discharge any capacitors before handling circuit boards or installing standoff hardware. Use the correct No. 4 screw and verify board hole alignment before seating. Follow applicable NEC guidelines for control panel assembly and enclosure work.