Electro Hardware P577M04F16-440 Round Female Standoff

Product Description

The ELECTRO HARDWARE P577M04F16-440 is a round female standoff designed to create fixed spacing between printed circuit boards, panels, and chassis components in electronic assemblies. Machined from aluminum alloy to material grade T-3 and finished bright with an anodized coating, this standoff meets the QQ-A-225A Comp 2 fastener standard. It features a 4-40 female thread with a full 1 inch thread depth, an overall length of 1.25 inches, and an outside diameter of 0.25 inches. The fully threaded interior accommodates 4-40 screws or studs on both ends, making it a straightforward choice for stacking or mounting tasks in tight enclosures.

This standoff is used in PCB assembly, control panel fabrication, and enclosure builds across electrical, electronics manufacturing, and light industrial applications. It is suited for residential and commercial control boards, instrument panels, and any low-voltage or signal-level assembly where precise board-to-board or board-to-chassis standoff height is required. Electricians, electronics technicians, and panel builders commonly specify this style of standoff when assembling or servicing control enclosures and DIN-rail mounted components.

Key Features

• 4-40 female thread, fully threaded to 1 inch depth for maximum fastener engagement
• Overall length of 1.25 inches with a tight length tolerance of -0.005 to 0.005 inches
• Outside diameter of 0.25 inches - compact profile for dense board layouts
• Aluminum construction, material grade T-3, with bright anodized finish for corrosion resistance
• Meets QQ-A-225A Comp 2 fastener standard
• Round body shape for consistent wrench or socket engagement during installation

Compatibility

Designed as an OEM-style replacement or new-installation standoff for electronic assemblies requiring a 4-40 threaded female hex or round standoff with a 1.25 inch overall length.

Installation Notes

Installation is typically performed by electronics technicians or panel builders using a small hex driver or open-end wrench sized to the 0.25 inch outside diameter. De-energize and discharge all circuits before working inside any control enclosure or PCB assembly. Avoid over-torquing into aluminum threads, as the material is softer than steel and susceptible to thread stripping under excessive force. Follow applicable NEC guidelines when installing standoffs inside listed electrical enclosures.