Electro Hardware S1351-M10-F21-I Circuit Board Spacer

Product Description

The ELECTRO HARDWARE S1351-M10-F21-I is a round, female unthreaded circuit board spacer designed to create precise standoff clearance between a PCB and its mounting surface. Constructed from Grade 2 steel with a zinc-plated finish, this spacer measures 0.375 inches overall length with a 0.5 inches outside diameter and a 0.194 inches inside diameter. It is sized for No. 10 screws and meets ASTM B633 and QQ-S-633 Type 1 finish standards. Electronics technicians, control board service techs, and industrial maintenance professionals install this type of fastener hardware during board mounting and enclosure assembly work.

This spacer is suited for use in residential and commercial electronic control assemblies, HVAC control board installations, and general electrical enclosure applications where a No. 10 screw pattern is specified. Its round body profile and female unthreaded design allow it to serve as a rigid standoff, maintaining consistent board-to-chassis separation and preventing contact shorts. The zinc-plated steel construction provides corrosion resistance appropriate for indoor panel and enclosure environments.

Key Features

• Female unthreaded round body accepts No. 10 screw hardware
• Grade 2 steel construction with zinc-plated finish per ASTM B633 and QQ-S-633 Type 1
• 0.375 inches overall length with tight length tolerance of -0.005 to 0.005 inches
• 0.5 inches outside diameter and 0.194 inches inside diameter with 0.000 to 0.010 inches ID tolerance
• Inch measurement system for direct compatibility with standard imperial fastener layouts

Compatibility

Designed as an OEM-style replacement or service spacer for circuit board mounting applications requiring a No. 10 screw, female unthreaded round standoff with a 3/8 inches overall length and 1/2 inches outside diameter.

Installation Notes

De-energize all control boards and electrical panels before removing or installing circuit board spacers. Use appropriately sized No. 10 fasteners and verify standoff seating is flush and secure before reinstalling the PCB. Follow applicable NEC guidelines for control panel work. Inspect zinc-plated finish for damage before installation in environments with elevated moisture exposure.