Gibraltar Z9090 Extra Thick Flat Washer 3/8 in Steel

Product Description

The GIBRALTAR Z9090 is an extra thick flat washer designed for use with 3/8-inch fasteners in heavy-duty mechanical and structural applications. Manufactured from grade 1005 case-hardened steel with a plain finish, this washer delivers the surface hardness needed to resist indentation and deformation under high-clamp loads. At 3/16 inches thick, it provides significantly more bearing surface than a standard flat washer, distributing load more effectively across the joint. The 7/16-inch inside diameter and 7/8-inch outside diameter suit standard 3/8-inch screw and bolt assemblies. Licensed trades and industrial maintenance professionals specify this washer where standard-thickness hardware is insufficient.

This washer is suited for residential and light commercial construction, HVAC equipment mounting, plumbing support hardware, electrical panel and conduit installations, and general mechanical assemblies where a larger bearing surface or increased thickness is required. The plain finish makes it appropriate for interior applications or situations where post-installation coating will be applied. It is sold individually but carries a minimum order quantity of 5 units per purchase.

Key Features

• Extra thick 3/16-inch body resists deformation under high-clamp loads
• Grade 1005 case-hardened steel construction for elevated surface hardness
• 7/16-inch inside diameter sized for 3/8-inch fasteners
• 7/8-inch outside diameter provides broad load distribution
• Plain finish compatible with interior use or field-applied coatings
• Inch-measurement system; UNSPSC Code 31161807

Compatibility

Designed as an OEM-style and aftermarket replacement flat washer for 3/8-inch screw and bolt assemblies in mechanical, structural, and trade-service applications.

Installation Notes

Install with standard wrenches or impact drivers appropriate for the fastener size. Verify that mating surfaces are clean and free of debris before seating the washer to ensure even load distribution. Power down or de-energize any electrical or mechanical system before servicing fastener assemblies in those systems. The plain finish offers no corrosion resistance, so avoid use in wet or outdoor environments unless a protective coating is applied.