Gibraltar Z8812 M12 Extra Thick Flat Washer Black Oxide

Product Description

The GIBRALTAR Z8812 is an M12 extra thick flat washer manufactured from case-hardened 1010 steel with a black oxide finish. It measures 13mm inside diameter, 22mm outside diameter, and 3mm thick. The case-hardening process increases surface hardness, improving resistance to deformation under load. The black oxide finish provides a degree of corrosion resistance while keeping surface reflectivity low. This washer is used by mechanical contractors, millwrights, maintenance technicians, and fabricators wherever an M12 fastener assembly requires a thicker-than-standard load-distributing washer.

This washer fits applications where a standard flat washer is insufficient for the clamping load or where added bearing surface area is needed to protect softer base materials. Typical uses include structural assemblies, equipment mounting, and general mechanical fastening in industrial, commercial, and trade settings. The metric sizing makes it appropriate for equipment and assemblies built to metric fastener standards.

Key Features

• Extra thick 3mm profile distributes clamp load over a wider bearing surface compared to standard flat washers
• Case-hardened 1010 steel construction resists deformation under high fastener torque
• Black oxide finish reduces surface reflection and provides mild corrosion resistance
• 13mm inside diameter sized for M12 fasteners
• 22mm outside diameter provides broad load-bearing footprint
• Metric dimensioning suits equipment and assemblies built to metric standards

Compatibility

Designed for use with M12 metric fastener assemblies in structural, mechanical, and industrial applications requiring an extra thick flat washer profile.

Installation Notes

Installation is performed by qualified tradespeople following applicable mechanical and structural fastening standards. Before service on any live equipment, ensure the system is de-energized, depressurized, or otherwise made safe before fastener work begins. Use calibrated torque tooling appropriate for M12 fasteners to achieve the specified clamp load without overloading the washer. Do not substitute this washer in applications specifying a different washer standard or material grade without engineering review.