Gibraltar Z9219 Extra Thick Flat Washer 1/2 in 18-8 Stainless

Product Description

The GIBRALTAR Z9219 is an extra thick flat washer designed for 1/2 inch screw applications requiring added load distribution and corrosion resistance. Manufactured from 18-8 stainless steel with a plain finish, this washer provides reliable performance in wet, outdoor, or chemically exposed environments. At 3/16 inches thick, it delivers more bearing surface than a standard flat washer, reducing fastener pull-through in softer materials. Trades including plumbing, HVAC, electrical, and general mechanical service use extra thick flat washers where vibration, heavy clamping loads, or substrate softness demand increased surface contact. The 0.05 pound unit weight makes it easy to handle on the job.

This washer fits 1/2 inch fasteners and is suited for use in residential and commercial mechanical systems, structural assemblies, equipment mounting, and general trade applications where stainless steel hardware is specified. The 18-8 stainless steel construction makes it appropriate for installations subject to moisture exposure, including rooftop HVAC equipment, outdoor plumbing connections, pool equipment enclosures, and marine-adjacent environments.

Key Features

• Extra thick design at 3/16 inches (0.1875 inches) for increased load distribution
• 18-8 stainless steel construction resists corrosion in wet and outdoor environments
• Inside diameter of 17/32 inches (0.5313 inches) fits 1/2 inch fasteners
• Outside diameter of 1-1/16 inches (1.0625 inches) provides broad bearing surface
• Plain finish with no additional coating — no adhesion or galvanic compatibility concerns
• Rockwell hardness C36 to C42 for consistent performance under clamping load

Compatibility

Designed for use with 1/2 inch screws and bolts in standard inch-measurement fastener assemblies requiring an extra thick flat washer profile.

Installation Notes

Install using standard hand tools; no specialized equipment is required for flat washer installation. Ensure the fastener and mating hardware are compatible with 18-8 stainless steel to avoid galvanic corrosion when joining dissimilar metals. Power down or de-energize any associated equipment before accessing fastened assemblies in electrical or mechanical panels. Follow applicable mechanical codes and equipment manufacturer torque guidelines when completing the fastened joint.