Electro Hardware P545M01F21-440 Round Female Standoff 4-40

Product Description

The ELECTRO HARDWARE P545M01F21-440 is a round female standoff designed to create fixed spacing between PCBs, panels, and enclosure components. Machined from brass with a zinc-plated finish, this fully threaded standoff accepts a 4-40 machine screw on both ends. It measures 0.75 inches overall length with a 0.25 inch outside diameter and a full 1 inch thread depth. The zinc plating meets ASTM B633 Type 1 and QQ-B-626 Comp 22 standards, providing corrosion resistance suitable for control panel and electronic assembly applications. Electricians, panel builders, and electronics technicians install this type of hardware during enclosure builds and PCB mounting assemblies.

This standoff is used in residential and commercial electrical enclosures, electronic control assemblies, and industrial panel builds where a 4-40 threaded female-to-female spacer is required. It is well suited for securing circuit boards, mounting plates, and subassemblies at a consistent 0.75 inch standoff height. The fully threaded interior allows fastener engagement from either end, making it adaptable to a range of stacking and mounting configurations.

Key Features

• Fully threaded female interior accepts 4-40 machine screws from both ends
• Brass construction with zinc-plated finish per ASTM B633 Type 1 and QQ-B-626 Comp 22
• Round body profile with 0.25 inch outside diameter for compact PCB and panel layouts
• 0.75 inch overall length with length tolerance of -0.005 to 0.005 inches
• 1 inch thread depth provides full fastener engagement through the standoff body

Compatibility

Designed as a standard 4-40 threaded round female standoff for use in PCB mounting, electrical enclosures, and panel assembly applications where inch-series fastener hardware is specified.

Installation Notes

Installation is typically performed by electricians or electronics technicians during panel assembly or PCB mounting operations. Ensure mating screws are 4-40 inch-series fasteners of appropriate length for the application. Do not overtighten, as brass is a softer material that can be damaged by excessive torque. Power down all circuits and discharge any capacitors before working inside electrical enclosures.