Gibraltar Z8950SS Stainless Steel Square Flat Washer

Product Description

The GIBRALTAR Z8950SS is a stainless steel square flat washer designed to distribute load evenly across bolted connections. Built for use with 1/4 inch fasteners, it features a 5/16 inch inside diameter, a 2 inch square outer profile, and a 1/4 inch thickness. Constructed from Grade 18-8 stainless steel, it resists corrosion in wet, outdoor, and chemically exposed environments. The uncoated finish maintains dimensional consistency and allows for direct contact with other stainless or compatible fastener hardware. Licensed tradespeople and experienced contractors install this type of washer in structural, mechanical, and equipment-mounting applications where standard round washers are not suitable.

This square flat washer is suited for residential and commercial installations requiring broad load distribution on soft substrates, oversized holes, or slotted mounting surfaces. Typical applications include HVAC equipment mounting, electrical panel and enclosure fastening, plumbing fixture attachment, and general structural assemblies. The square geometry resists rotation during torquing, making it useful in single-wrench access situations.

Key Features

• Grade 18-8 stainless steel construction for corrosion resistance in wet and outdoor environments
• Square profile provides broader surface contact and resists washer rotation during installation
• 5/16 inch inside diameter fits standard 1/4 inch bolt shanks with appropriate clearance
• 1/4 inch thickness offers rigid load distribution on uneven or soft mounting surfaces
• Uncoated finish maintains consistent dimensions and avoids coating interference at fastener interfaces

Compatibility

Designed for use with 1/4 inch bolts and fasteners requiring a 5/16 inch minimum hole clearance. Suitable as an OEM-style or replacement flat washer in structural and mechanical fastening assemblies across HVAC, plumbing, and electrical applications.

Installation Notes

Installation is performed by licensed HVAC technicians, plumbers, electricians, or general contractors depending on the application. De-energize electrical systems and shut off any relevant utilities before accessing fastened assemblies. Use appropriate torque practices for stainless fasteners to avoid galling — apply anti-seize compound to mating threads when pairing stainless washers with stainless bolts and nuts. Follow applicable codes including NEC, IPC, or IFGC as required by the specific installation context.