Gibraltar Z9160 Extra Thick Flat Washer 18-8 Stainless Steel

Product Description

The GIBRALTAR Z9160 is an extra thick flat washer designed for use with No. 8 screws. Manufactured from 18-8 stainless steel with a plain finish, this washer provides reliable load distribution and corrosion resistance in demanding fastener applications. The inside diameter measures 3/16 inches and the outside diameter measures 7/16 inches, with a thickness of 5/64 inches. The increased thickness compared to standard flat washers adds mechanical strength and reduces the risk of pull-through under load. Hardness is rated at Rockwell C36-C42. Electricians, plumbers, HVAC technicians, and general tradespeople use washers of this type when a more robust bearing surface is required at fastener joints.

This washer is suited for light-duty fastener assemblies involving No. 8 screws where corrosion resistance is a priority, such as outdoor installations, wet environments, or applications involving dissimilar metals. The 18-8 stainless steel grade resists oxidation and mild chemical exposure, making it a practical choice for plumbing, electrical enclosure work, HVAC equipment mounting, and similar trade applications. Sold individually per package with a minimum order quantity of 5 units.

Key Features

• Extra thick profile at 5/64 inches provides greater bearing surface than standard flat washers
• 18-8 stainless steel construction resists corrosion and oxidation
• Plain finish with no coating — suitable for use with stainless fasteners to avoid galvanic incompatibility
• Hardness rated Rockwell C36-C42 for mechanical durability under load
• Inside diameter 3/16 inches fits No. 8 screw shafts cleanly
• Inch measurement system; all dimensions verified to four-decimal precision

Compatibility

Designed for use with No. 8 screws in inch-measurement fastener assemblies requiring an extra thick flat washer in 18-8 stainless steel.

Installation Notes

Installation requires no specialty tools beyond standard hand or power drivers appropriate to the mating fastener. When pairing with stainless steel screws, avoid mixing with carbon steel fasteners to prevent galvanic corrosion. Always ensure the washer seats flat against the mating surface before applying torque to the fastener. Inspect washers for deformation or cracking if reusing in high-cycle applications.