Midwest Fasteners Class 8 Zinc Plated Steel Metric Nylon Insert Lock Nut

Midwest Fasteners Class 8 Zinc Plated Steel Metric Nylon Insert Lock Nut

Midwest Fasteners' Class 8 nylon insert lock nut is available as a full metric size family, ranging from 4mm-.7 up through 16mm-1.5 and covering common pitches such as 6mm-1.0, 8mm-1.25, 10mm-1.5, and 12mm-1.75. Every size in this family is built from steel with a zinc finish for corrosion resistance and uses the same internal nylon insert to deliver friction-based locking action that resists loosening under vibration and repeated load cycling. Whichever size you select, this nylon insert lock nut is engineered for repeated use in demanding assembly, maintenance, and fabrication work where a secure, reusable mechanical lock is required.

Key Features

• Size Range: Available across 14 metric sizes from 4mm-.7 to 16mm-1.5, including 4mm, 5mm, 6mm, 7mm, 8mm, 10mm, 12mm, 14mm, and 16mm diameters with multiple thread pitches per size.
• Full Size List: 4mm-.7, 5mm-.8, 6mm-1.0, 7mm-1.0, 8mm-1.0, 8mm-1.25, 10mm-1.5, 10mm-1.25, 10mm-1.0, 12mm-1.5, 12mm-1.75, 12mm-1.25, 14mm-1.5, and 16mm-1.5 are all part of this family.
• Product Type: Nylon insert lock nut designed to resist loosening from vibration and repeated load cycling.
• Material & Finish: Steel construction with a zinc finish for added corrosion resistance in general shop and outdoor-adjacent use.
• Grade: Class 8 steel strength class applied across every size in the family.
• Locking Action: Internal nylon insert grips the mating bolt or screw threads to maintain clamp load and prevent back-off.
• Reusability: The nylon insert design allows the nut to be removed and reinstalled while retaining locking performance for routine maintenance work.

Technical Specifications

• Product Size: 4mm - 16mm

Typical Applications

• Machinery and equipment assemblies subject to vibration where standard hex nuts tend to loosen.
• Automotive, trailer, and equipment maintenance requiring a fastener that holds under repeated motion and stress.
• Structural and fabrication assemblies requiring a reusable, mechanically locking nut.
• General maintenance and repair work where corrosion resistance from the zinc finish is beneficial.
• Shop and jobsite hardware kits paired with matching-thread metric bolts, screws, and studs across the full 4mm-16mm size range.

Why Midwest Fasteners?

Midwest Fasteners builds this Class 8 steel nylon insert lock nut family with a zinc finish to deliver consistent locking performance and corrosion resistance across repeated installs, no matter which of the 14 metric sizes your job requires. For contractors, maintenance techs, and fabricators who need a nut that stays put under vibration across a full 4mm to 16mm metric range, this lock nut family offers a dependable, reusable locking solution backed by clearly stated material and grade specifications across every size.