{
  "category": "Hex Nuts",
  "vertical": "fastener-distribution",
  "source": "https://getclaro.ai/resources/attribute-library/fastener-distribution/hex-nuts/",
  "status": "editorial-draft",
  "note": "Editorial reference template. Example values show format only and do not describe a real SKU. Not an official ETIM or ECLASS class.",
  "groups": [
    {
      "key": "identity",
      "name": "Identity",
      "check": "Preserve leading zeros and punctuation, validate against the manufacturer record, and check the GTIN check digit and packaging level before linking."
    },
    {
      "key": "technical",
      "name": "Technical specifications",
      "check": "Store the number and unit separately. Convert only when the source unit and test conditions are known."
    },
    {
      "key": "selection",
      "name": "Selection attributes",
      "check": "Map supplier wording to a governed vocabulary only after checking the source text and which variant it applies to."
    },
    {
      "key": "fit",
      "name": "Fit & compatibility",
      "check": "Keep model and series qualifiers. A similar-looking part is not a verified fit until a source says so."
    },
    {
      "key": "evidence",
      "name": "Evidence & compliance",
      "check": "Link the manufacturer document or label with its edition or date. Never copy a certification from a neighboring SKU."
    }
  ],
  "fields": [
    {
      "key": "nut_style",
      "label": "Nut Style",
      "group": "selection",
      "priority": "core",
      "value_type": "controlled",
      "unit": null,
      "example_format": "Heavy Hex"
    },
    {
      "key": "dia_thread_size_nominal",
      "label": "Dia./Thread Size (Nominal)",
      "group": "technical",
      "priority": "core",
      "value_type": "text",
      "unit": null,
      "example_format": "1/2-13"
    },
    {
      "key": "thread_series_pitch",
      "label": "Thread Series / Pitch",
      "group": "fit",
      "priority": "core",
      "value_type": "controlled",
      "unit": null,
      "example_format": "UNC"
    },
    {
      "key": "material",
      "label": "Material",
      "group": "selection",
      "priority": "core",
      "value_type": "controlled",
      "unit": null,
      "example_format": "Medium carbon steel, quenched and tempered"
    },
    {
      "key": "grade_property_class",
      "label": "Grade / Property Class",
      "group": "selection",
      "priority": "core",
      "value_type": "controlled",
      "unit": null,
      "example_format": "ASTM A563 Grade DH"
    },
    {
      "key": "finish_coating",
      "label": "Finish / Coating",
      "group": "selection",
      "priority": "core",
      "value_type": "controlled",
      "unit": null,
      "example_format": "Hot-dip galvanized (ASTM F2329)"
    },
    {
      "key": "width_across_flats",
      "label": "Width Across Flats",
      "group": "technical",
      "priority": "core",
      "value_type": "number",
      "unit": "in",
      "example_format": "7/8 in"
    },
    {
      "key": "nut_height_thickness",
      "label": "Nut Height (Thickness)",
      "group": "technical",
      "priority": "core",
      "value_type": "number",
      "unit": "in",
      "example_format": "31/64 in"
    },
    {
      "key": "manufacturer_part_number",
      "label": "Manufacturer Part Number",
      "group": "identity",
      "priority": "core",
      "value_type": "identifier",
      "unit": null,
      "example_format": "HHN-DH-050-HDG"
    },
    {
      "key": "thread_class_of_fit",
      "label": "Thread Class of Fit",
      "group": "fit",
      "priority": "differentiating",
      "value_type": "controlled",
      "unit": null,
      "example_format": "2B"
    },
    {
      "key": "thread_direction",
      "label": "Thread Direction",
      "group": "fit",
      "priority": "differentiating",
      "value_type": "controlled",
      "unit": null,
      "example_format": "Right hand"
    },
    {
      "key": "proof_load_stress",
      "label": "Proof Load Stress",
      "group": "technical",
      "priority": "differentiating",
      "value_type": "number",
      "unit": "psi",
      "example_format": "150,000 psi (A563 DH, hot-dip galvanized)"
    },
    {
      "key": "overtapped_for_coating",
      "label": "Overtapped for Coating",
      "group": "selection",
      "priority": "differentiating",
      "value_type": "controlled",
      "unit": null,
      "example_format": "Yes, overtapped for hot-dip galvanizing"
    },
    {
      "key": "mating_bolt_specification",
      "label": "Mating Bolt Specification",
      "group": "fit",
      "priority": "differentiating",
      "value_type": "text",
      "unit": null,
      "example_format": "ASTM F3125 Grade A325"
    },
    {
      "key": "hardness",
      "label": "Hardness",
      "group": "technical",
      "priority": "differentiating",
      "value_type": "text",
      "unit": "HRC",
      "example_format": "24-38 HRC"
    },
    {
      "key": "dimensional_standard",
      "label": "Dimensional Standard",
      "group": "evidence",
      "priority": "channel",
      "value_type": "controlled",
      "unit": null,
      "example_format": "ASME B18.2.2"
    },
    {
      "key": "country_of_melt_and_manufacture",
      "label": "Country of Melt and Manufacture",
      "group": "evidence",
      "priority": "channel",
      "value_type": "controlled",
      "unit": null,
      "example_format": "Melted and manufactured in USA"
    },
    {
      "key": "certification_available",
      "label": "Certification Available",
      "group": "evidence",
      "priority": "channel",
      "value_type": "controlled",
      "unit": null,
      "example_format": "MTR, lot traceable (EN 10204 3.1)"
    }
  ],
  "evidence_columns": [
    "raw_value",
    "normalized_value",
    "source_uri",
    "source_page_or_row",
    "confidence",
    "review_state",
    "last_verified"
  ],
  "normalization_examples": [
    {
      "attribute": "Grade / Property Class",
      "variants": [
        "GR 8",
        "Grade 8",
        "G8",
        "Gr.8",
        "GR8",
        "SAE Gr 8"
      ],
      "normalized": "SAE J995 Grade 8"
    },
    {
      "attribute": "Finish / Coating",
      "variants": [
        "HDG",
        "Hot Dip Galv",
        "Hot-Dipped Galvanized",
        "HD Galv",
        "Zinc, Hot Dip",
        "Hot Dip Galvanised"
      ],
      "normalized": "Hot-Dip Galvanized (ASTM F2329)"
    },
    {
      "attribute": "Dia./Thread Size",
      "variants": [
        "1/2-13",
        "1/2\"-13 UNC",
        ".500-13",
        "1/2 in.-13 UNC-2B",
        "0.5-13"
      ],
      "normalized": "1/2-13 UNC"
    }
  ]
}