ISO 8675 (GB/T 6173) Fine Pitch Thin Hexagon Nuts, commonly referred to as low-profile hex jam nuts or fine thread thin nuts, are precision-threaded mechanical fasteners engineered for space-restricted assemblies or secondary locking applications.

Unlike standard coarse thread nuts, the metric fine thread pitch provides a smaller helix angle and greater friction engagement per axial millimeter. This design allows for superior precision in axial adjustment, resistance to vibration loosening, and structural stability in compact machinery.

• Zinc Plated Carbon Steel (Cr3+ Blue/White Zinc): Manufactured from Class 04/05 structural carbon steel and finished with eco-friendly trivalent zinc plating. Offers excellent tensile load capacity and reliable rust protection for indoor machinery and industrial equipment.
• 304 Stainless Steel (Plain / Passivated): Crafted from A2-70 grade austenitic stainless steel with a natural clean finish. Delivers high resistance to corrosion, oxidation, and chemicals, making it ideal for marine, outdoor, chemical, and food processing applications.

• Space-Saving Low Profile: Height is approximately half of a standard hex nut (h ≈ 0.5d), ideal for tight clearance spaces and valve stem lockings.
• Enhanced Fine Thread Precision: Smaller pitch allows precise torque calibration and micrometer-level axial positioning.
• Vibration Resistant: Increased friction contact prevents self-loosening under continuous vibration loads.
• Double Chamfered Design: Manufactured with Type B chamfered edges on both sides for easy wrench engagement and assembly aesthetic.

• Hydraulics & Pneumatics: Cylinder rod end locks, hydraulic hose fittings, and control valve mounts.
• Automotive Powertrain: Sensor brackets, shift linkage positioning, and steering rod lock nuts.
• Precision Instruments: Fine axial adjustment stops, optical positioning mounts, and calibrated spindles.
• Industrial Machinery: Limit switch brackets, compact linear actuator mounts, and motor housings.

What is the difference between ISO 8675 and ISO 4035?
Both are metric thin hex nuts, but ISO 8675 specifies Metric Fine Pitch Thread, whereas ISO 4035 specifies Standard Coarse Pitch Thread.

How is an ISO 8675 thin nut used as a jam nut?
In jam nut configurations, the thin nut is threaded first and torqued against the bearing surface, followed by a standard thickness nut. Tightening the standard nut against the thin nut locks both in place via axial tension.

Can you manufacture non-standard fine pitches or custom materials?
Yes, we support custom pitches (e.g., M10×0.75, M18×1.0) and materials including 316 Stainless Steel, Brass, and Alloy Steel.