Midwest Fasteners Zinc Plated Steel Fine Thread Slotted Castle Hex Nut

Midwest Fasteners Zinc Plated Steel Fine Thread Slotted Castle Hex Nut

The Midwest Fasteners Castle Hex Nut is a fine thread, slotted hex nut machined from steel and finished in zinc plating for dependable corrosion resistance on jobs that call for a cotter pin or safety wire to lock the nut in place. Also known as a slotted hex nut, this castle-style nut has the signature slotted crown that lets a cotter pin pass through a drilled bolt or stud shank, keeping the nut from backing off under vibration. This fine thread castle nut family is available in sizes from 1/4"-28 through 7/8"-14, including 3/8"-24, 7/16"-20, 9/16"-18, 5/8"-18, and 3/4"-16, so the correct size can be matched to the mating fine thread bolt or stud. Manufactured in the United States, each nut carries a silver zinc finish that protects the steel base material from rust in shop, automotive and machinery environments; confirm fine thread pitch compatibility before installing on any application that calls for a slotted or castellated locking nut.

Key Features

• Size Range: Fine thread sizes from 1/4"-28 up to 7/8"-14, covering 3/8"-24, 7/16"-20, 9/16"-18, 5/8"-18, and 3/4"-16.
• Material & Finish: Steel construction with a zinc plated finish for added corrosion resistance and a clean silver appearance.
• Thread: Fine thread pitch for applications requiring finer, more precise thread engagement than standard coarse thread hardware.
• Product Type: Slotted hex nut, commonly called a castle nut, designed to accept a cotter pin or safety wire through its slotted crown.
• Locking Function: The slotted design lets a cotter pin or locking wire pass through the bolt and nut, securing the connection against loosening from vibration.
• Color: Silver zinc finish typical of plated steel fasteners.
• Country of Origin: Manufactured in the United States.

Technical Specifications

• Product Size: 1/4" - 7/8"

Typical Applications

• Securing wheel bearings, spindle nuts, and axle assemblies where a cotter pin is required for positive locking.
• Automotive and trailer suspension components needing a vibration-resistant, pinned connection.
• Machinery and equipment assemblies where fine thread hardware is specified for precise fit-up.
• General maintenance and repair work requiring a zinc plated steel castle nut for corrosion resistance across a range of fine thread sizes.

Why Midwest Fasteners?

Midwest Fasteners produces this castle hex nut family from steel with a consistent zinc finish, giving contractors and maintenance techs a dependable, corrosion-resistant locking nut for fine thread applications across the full 1/4"-28 to 7/8"-14 size range. Made in the United States, it delivers the sizing and finish consistency professionals expect when a slotted nut and cotter pin combination is needed to keep a critical connection from backing off under vibration.