Electro Hardware P577M10F21-440 Round Female Standoff

Product Description

The ELECTRO HARDWARE P577M10F21-440 is a round female standoff designed for use in electronic assemblies, control panels, and chassis builds where secure, threaded spacing between components is required. Machined from Grade 2 steel with a zinc-plated finish that meets ASTM B633 Type 1 and QQ-S-633 standards, this standoff provides corrosion resistance suitable for indoor electrical enclosures. It features a 4-40 thread size, a 1.25-inch overall length, and a 0.25-inch outside diameter. The fully threaded interior accepts a standard 4-40 fastener to a depth of 1 inch, allowing reliable engagement with mating hardware. Electricians, panel builders, and electronics technicians install these standoffs during enclosure fabrication and board mounting work.

This standoff is well suited for residential and commercial control panel assemblies, printed circuit board mounting, and electronic chassis construction. The inch-system sizing and 4-40 thread make it compatible with a wide range of standard fastener hardware used in low-voltage control wiring, instrument enclosures, and electronic sub-assemblies. It is particularly useful wherever a fixed, non-collapsing spacer is needed to maintain consistent clearance between mounted components.

Key Features

• 4-40 thread size, fully threaded interior for reliable fastener engagement
• 1 inch thread depth provides full engagement for standard 4-40 fasteners
• 1.25-inch overall length for consistent component spacing
• 0.25-inch outside diameter in a round body profile
• Grade 2 steel construction with zinc-plated finish
• Meets ASTM B633 Type 1 and QQ-S-633 finish standards

Compatibility

Designed as a standard inch-series female standoff for use with 4-40 threaded fasteners in electronic enclosures, control panels, and PCB mounting applications.

Installation Notes

Installation is performed by electricians, panel builders, and electronics technicians using standard hand tools. De-energize all circuits in the enclosure before installing or removing standoffs in live panels. Avoid overtightening mating screws, as the 4-40 thread is fine-pitched and can be damaged by excessive torque. Follow applicable NEC guidelines when installing hardware inside electrical enclosures.