Gibraltar Z9154-5 Extra Thick Flat Washer 18-8 Stainless

Product Description

The GIBRALTAR Z9154-5 is a size 4 screw extra thick flat washer manufactured from 18-8 stainless steel with a plain finish. Flat washers of this type distribute load across fastener bearing surfaces, reducing stress concentration and protecting the clamped material. The extra thick profile adds rigidity over standard flat washers, making it suitable for applications where greater load distribution or gap-filling is required. With an inside diameter of 0.125 inches and an outside diameter of 0.250 inches, this washer is sized for No. 4 screws. Hardness is rated at Rockwell C36-C42. Installation is performed by plumbers, electricians, HVAC technicians, and general tradespeople as part of fastener assemblies in corrosion-prone environments.

This washer is suited for use in residential and light commercial applications where corrosion resistance is a priority. The 18-8 stainless steel construction holds up in wet, humid, or chemically active environments, including plumbing chases, electrical enclosures, HVAC equipment panels, and pool equipment installations. The plain finish leaves the stainless surface uncoated, preserving its natural corrosion resistance without added plating.

Key Features

• Extra thick profile provides greater load distribution than standard flat washers
• 18-8 stainless steel construction resists corrosion in wet and humid environments
• Plain finish preserves the natural corrosion resistance of the stainless base material
• Inside diameter of 0.125 inches fits No. 4 screw shanks
• Rockwell C36-C42 hardness rating for reliable performance under load
• Inch measurement system; dimensions confirmed to four decimal places

Compatibility

Designed for use with No. 4 screws in standard inch-measurement fastener assemblies requiring an extra thick flat washer profile.

Installation Notes

Install using standard hand tools appropriate for the fastener size. Ensure mating surfaces are clean and free of debris before seating the washer. Stainless steel fasteners can be prone to galling; apply anti-seize compound to threads when torquing in stainless-to-stainless assemblies if recommended by the fastener system design. Follow applicable mechanical codes for the trade and application involved.