Gibraltar Z8844 M5 Extra Thick Flat Washer Black Oxide

Product Description

The GIBRALTAR Z8844 is an M5 extra thick flat washer manufactured from case-hardened 1010 steel with a black oxide finish. It measures 5.3mm inside diameter, 15mm outside diameter, and 3.5mm thick, providing a substantially greater load-bearing surface and clamping depth than standard flat washers of the same screw size. The black oxide finish offers mild corrosion resistance and reduces light reflection in finished assemblies. Weighing 0.01 pounds per piece, this washer is suited for mechanical, structural, and general fastening applications where standard washer thickness is insufficient.

This washer is used in metric fastening applications requiring a thick, rigid bearing surface under an M5 fastener head or nut. Typical install scenarios include machinery assembly, equipment mounting, sheet metal fabrication, and structural bracketing where load distribution over a larger area is required. It is a metric-standard component and is commonly specified by maintenance technicians, millwrights, and general tradespeople working with M5 hardware.

Key Features

• Extra thick profile at 3.5mm provides greater load distribution than standard flat washers
• Case-hardened 1010 steel construction resists deformation under high clamp loads
• Black oxide finish provides mild corrosion resistance and a non-reflective appearance
• 5.3mm ID fits M5 screws and bolts with minimal clearance for accurate centering
• 15mm OD spreads bearing load across a wider surface area
• Metric dimensional standard for use in metric fastening systems

Compatibility

Designed as a metric flat washer for use with M5 screws and bolts in general mechanical and structural fastening applications.

Installation Notes

Installation requires no special tools beyond standard hand tools for the associated fastener. Ensure mating surfaces are clean and free of debris before seating the washer to maintain full bearing contact. Do not substitute this washer in applications requiring a specific hardness grade or load rating without confirming the 1010 case-hardened steel specification meets the engineering requirement. Follow applicable mechanical or structural codes for the assembly in which this fastener hardware is used.