Gibraltar Z8856 M16 Extra Thick Flat Washer Black Oxide

Product Description

The GIBRALTAR Z8856 is an extra thick flat washer engineered for M16 metric fastener applications. Manufactured from 1010 case-hardened steel with a black oxide finish, this washer delivers improved load distribution and surface protection in demanding mechanical assemblies. The extra thick profile — 5mm through — provides greater resistance to deformation under high-clamp-load conditions compared to standard flat washers. The black oxide coating reduces surface corrosion and minimizes light reflection in finished assemblies. Plumbers, pipefitters, millwrights, and general industrial mechanics reach for this type of washer when standard thickness is insufficient for the joint or fastener specification.

This washer suits metric fastener applications across commercial and industrial settings, including structural connections, equipment mounting, and piping support systems where M16 bolts or screws are specified. The 17mm inside diameter clears an M16 fastener shank cleanly while the 32mm outside diameter spreads bearing load across the mating surface. It is sold individually and is well-suited for maintenance, repair, and operations (MRO) stock as well as production assembly lines requiring metric hardware.

Key Features

• Extra thick 5mm profile resists deformation under high-clamp-load fastening
• Case-hardened 1010 steel construction for improved surface hardness and durability
• Black oxide finish reduces corrosion and minimizes surface glare
• 17mm inside diameter provides clean clearance for M16 fastener shanks
• 32mm outside diameter distributes bearing load across the mating surface
• Metric sizing per standard M16 fastener specifications

Compatibility

Designed for use with M16 metric screws and bolts. Fits any application requiring a flat washer with a 17mm inside diameter and 32mm outside diameter in metric-standard assemblies.

Installation Notes

Install using standard hand or power tools appropriate for M16 fastener hardware. Ensure mating surfaces are clean and free of debris before seating the washer to maintain proper load distribution. Follow applicable mechanical and structural codes for fastener torque and joint specifications on the assembly being serviced. Do not substitute this washer in applications requiring a different inside diameter, outside diameter, or hardness rating than specified.