Electro Hardware 1435M12F21-440 Hex Standoff 4-40

Product Description

The ELECTRO HARDWARE 1435M12F21-440 is a male-female hex circuit board standoff designed to create a fixed, measured gap between stacked PCBs or between a board and a chassis. It features a 4-40 threaded male end on one side and a 4-40 threaded female end on the other, allowing boards to be secured and spaced in a single fastener step. The standoff is manufactured from Grade 2 steel with a zinc-plated finish meeting ASTM B633 Type 1 and QQ-S-633 standards. Overall length is 0.6875 inches, with a hex body width across flats of 0.25 inches. Electricians, electronics technicians, and control board service professionals use this type of standoff when mounting or servicing PCBs in HVAC control panels, electrical enclosures, and related equipment.

This standoff is suited for residential and light commercial applications wherever 4-40 threaded circuit board mounting is required. Typical install scenarios include securing control boards inside HVAC air handlers, furnace control enclosures, and electrical panel subassemblies. The hex body shape allows installation and removal with standard hex drivers or wrenches, making it practical for tight enclosure spaces. The zinc-plated steel construction provides corrosion resistance appropriate for indoor control panel environments.

Key Features

• Male-female thread configuration accepts 4-40 fasteners on both ends for stackable board mounting
• Hex body profile allows wrench or driver engagement for controlled installation torque
• Zinc-plated steel finish meets ASTM B633 Type 1 and QQ-S-633 corrosion resistance standards
• Grade 2 steel construction for consistent thread engagement and dimensional accuracy
• Overall length of 0.6875 inches with a length tolerance of -0.005 to 0.005 inches
• Body length of 0.5 inches with a 3/16-inch thread length on the male end

Compatibility

Designed for use in any application requiring a 4-40 male-female hex standoff with a 0.6875-inch overall length and 0.25-inch width across flats, including PCB mounting in HVAC control enclosures, electrical panels, and electronic assemblies.

Installation Notes

Installation is typically performed by electricians or electronics technicians during control board assembly or replacement. Disconnect and lock out all power to the enclosure before removing or installing circuit board standoffs. Use an appropriately sized hex wrench or nut driver on the hex body to seat the standoff without overtightening, which can strip the 4-40 threads. Follow applicable NEC guidelines when working inside electrical enclosures.