{
 "version": "2026-10-20",
 "license": "Dimension sheets: CC BY 4.0. Standard and published-size files: CC BY 4.0. Xem Studio's own designs (files_license = Xem Studio Design License): free to use and sell things from, not to redistribute as files — https://xemstudio.com/license/. Other publishers' files: their own license, linked beside them.",
 "slug": "spring-lock-washers-din-127-b",
 "name": "Spring lock washers, DIN 127 B (split washers, rectangular section): M2–M100 bore, outside diameter, width, thickness, free height",
 "kind": "standard",
 "category": "Hardware",
 "group": "Fasteners",
 "year": null,
 "question": "What are the dimensions of a DIN 127 B spring washer, and what is the outside diameter of an M8 split lock washer?",
 "tags": [
  "split washer",
  "spring washer",
  "lock washer",
  "din 127",
  "din 127 b",
  "helical spring washer",
  "fastener",
  "tool"
 ],
 "aliases": [
  "din 127 b dimensions",
  "m8 spring washer dimensions",
  "m10 split lock washer outside diameter",
  "m6 spring washer thickness",
  "din 127 m12",
  "lock washer m5 dimensions",
  "m3 split washer size",
  "din 127 b m16 17 mm",
  "spring washer free height",
  "split lock washer metric size chart",
  "din 127 b vs din 6798"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "not-scanned",
 "les": false,
 "free_files": 0,
 "url": "https://xemstudio.com/objects/spring-lock-washers-din-127-b/",
 "sheet_txt": "https://xemstudio.com/objects/spring-lock-washers-din-127-b/sheet.txt",
 "sheet": {
  "basis": "Westfield Fasteners' DIN 127 table (type B, 2 to 100 mm), cross-checked on 15 sizes against McMaster-Carr's DIN 127B lock washer listing (ID, OD, thickness range); numbers only",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "DIN 127 B is the helical spring (split) lock washer with square ends and rectangular section. Columns (mm): d1 bore min and max; d2 outside max; b width of section; s thickness; h free height of type B, min and max; r as printed. Rows b and s are 19 values per table after the label cell: the page's own markup puts a dash in the label column (limit column), so the dash is not a value. McMaster-Carr's thickness ranges agree with s on all 15 sizes compared (e.g. M6 1.5 to 1.7 against s 1.6; M10 2.0 to 2.4 against s 2.2; M24 4.8 to 5.2 against s 5), and McMaster's ID / OD equal d1 max and d2 max for those sizes.",
   "The last column shows McMaster-Carr's ID / OD / thickness range for the sizes it lists (M2, M2.5, M3, M4, M5, M6, M8, M10, M12, M16, M20, M24, M30, M36, M48). McMaster prints no width b. McMaster lists a few alternatives by finish (M3.5 3.9 or 3.6 mm bore in zinc steel; M27 27.5 or 28.5 mm) as printed there; Westfield's d1 for M27 is 27.5 min / 28.5 max, which explains the second value.",
   "One printed anomaly dropped: Westfield's type B minimum free height for size 39 reads 2 (neighbours 12 and 14); it is shown as a typo and left out. Sizes above M24 are given by their nominal size only on the Westfield table (sizes 30 to 100 have no M prefix in the header).",
   "Westfield's notes: DIN 127 applies to assemblies up to property class 5.8, reverse coil is recommended for left-hand threads, and type A (with prongs) is not tabulated here. The washer free height h is the coil height before tightening; the flat-state geometry (coil pitch, cut angle) is not given as numbers in the sources read, so no model is drawn.",
   "McMaster-Carr sells DIN 127B lock washers with per-part STEP; its DIN 127B category is linked, not copied."
  ],
  "table": {
   "columns": [
    "size",
    "d1 min",
    "d1 max",
    "d2 max",
    "b",
    "s",
    "h type B min",
    "h type B max",
    "r",
    "McMaster ID / OD / thickness"
   ],
   "rows": [
    [
     "M2",
     "2.1",
     "2.4",
     "4.4",
     "0.9",
     "0.5",
     "1",
     "1.2",
     "0.1",
     "2.4 / 4.4 / 0.4 to 0.6"
    ],
    [
     "M2.2",
     "2.3",
     "2.6",
     "4.8",
     "1",
     "0.6",
     "1.2",
     "1.4",
     "0.1",
     "—"
    ],
    [
     "M2.5",
     "2.6",
     "2.9",
     "5.1",
     "1",
     "0.6",
     "1.2",
     "1.4",
     "0.1",
     "2.9 / 5.1 / 0.5 to 0.7"
    ],
    [
     "M3",
     "3.1",
     "3.4",
     "6.2",
     "1.3",
     "0.8",
     "1.6",
     "1.9",
     "0.2",
     "3.4 / 6.2 / 0.7 to 0.9"
    ],
    [
     "M3.5",
     "3.6",
     "3.9",
     "6.7",
     "1.3",
     "0.8",
     "1.6",
     "1.9",
     "0.2",
     "—"
    ],
    [
     "M4",
     "4.1",
     "4.4",
     "7.6",
     "1.5",
     "0.9",
     "1.8",
     "2.1",
     "0.2",
     "4.4 / 7.6 / 0.8 to 1.0"
    ],
    [
     "M5",
     "5.1",
     "5.4",
     "9.2",
     "1.8",
     "1.2",
     "2.4",
     "2.8",
     "0.2",
     "5.4 / 9.2 / 1.1 to 1.3"
    ],
    [
     "M6",
     "6.1",
     "6.5",
     "11.8",
     "2.5",
     "1.6",
     "3.2",
     "3.8",
     "0.3",
     "6.5 / 11.8 / 1.5 to 1.7"
    ],
    [
     "M7",
     "7.1",
     "7.5",
     "12.8",
     "2.5",
     "1.6",
     "3.2",
     "3.8",
     "0.3",
     "—"
    ],
    [
     "M8",
     "8.1",
     "8.5",
     "14.8",
     "3",
     "2",
     "4",
     "4.7",
     "0.5",
     "8.5 / 14.8 / 1.9 to 2.1"
    ],
    [
     "M10",
     "10.2",
     "10.7",
     "18.1",
     "3.5",
     "2.2",
     "4.4",
     "5.2",
     "0.5",
     "10.7 / 18.1 / 2.0 to 2.4"
    ],
    [
     "M12",
     "12.2",
     "12.7",
     "21.1",
     "4",
     "2.5",
     "5",
     "5.9",
     "1",
     "12.7 / 21.1 / 2.3 to 2.7"
    ],
    [
     "M14",
     "14.2",
     "14.7",
     "24.1",
     "4.5",
     "3",
     "6",
     "7.1",
     "1",
     "—"
    ],
    [
     "M16",
     "16.2",
     "17",
     "27.4",
     "5",
     "3.5",
     "7",
     "8.3",
     "1",
     "17.0 / 27.4 / 3.3 to 3.7"
    ],
    [
     "M18",
     "18.2",
     "19",
     "29.4",
     "5",
     "3.5",
     "7",
     "8.3",
     "1",
     "—"
    ],
    [
     "M20",
     "20.2",
     "21.2",
     "33.6",
     "6",
     "4",
     "8",
     "9.4",
     "1",
     "21.2 / 33.6 / 3.8 to 4.2"
    ],
    [
     "M22",
     "22.5",
     "23.5",
     "35.9",
     "6",
     "4",
     "8",
     "9.4",
     "1",
     "—"
    ],
    [
     "M24",
     "24.5",
     "25.5",
     "40",
     "7",
     "5",
     "10",
     "11.8",
     "1.6",
     "25.5 / 40.0 / 4.8 to 5.2"
    ],
    [
     "M27",
     "27.5",
     "28.5",
     "43",
     "7",
     "5",
     "10",
     "11.8",
     "1.6",
     "—"
    ],
    [
     "M30",
     "30.5",
     "31.7",
     "48.2",
     "8",
     "6",
     "12",
     "14.2",
     "1.6",
     "31.7 / 48.2 / 5.8 to 6.2"
    ],
    [
     "M36",
     "36.5",
     "37.7",
     "58.2",
     "10",
     "6",
     "12",
     "14.2",
     "1.6",
     "37.7 / 58.2 / 5.8 to 6.2"
    ],
    [
     "M39",
     "39.5",
     "40.7",
     "61.2",
     "10",
     "6",
     "— (printed 2; typo)",
     "14.2",
     "1.6",
     "—"
    ],
    [
     "42",
     "42.5",
     "43.7",
     "68.2",
     "12",
     "7",
     "14",
     "16.5",
     "2",
     "—"
    ],
    [
     "45",
     "45.5",
     "46.7",
     "71.2",
     "12",
     "7",
     "14",
     "16.5",
     "2",
     "—"
    ],
    [
     "48",
     "49",
     "50.5",
     "75",
     "12",
     "7",
     "14",
     "16.5",
     "2",
     "50.5 / 75.0 / 6.8 to 7.2"
    ],
    [
     "52",
     "53",
     "54.5",
     "83",
     "14",
     "8",
     "16",
     "18.9",
     "2",
     "—"
    ],
    [
     "56",
     "57",
     "58.5",
     "87",
     "14",
     "8",
     "16",
     "18.9",
     "2",
     "—"
    ],
    [
     "60",
     "61",
     "62.5",
     "91",
     "14",
     "8",
     "16",
     "18.9",
     "2",
     "—"
    ],
    [
     "64",
     "65",
     "66.5",
     "95",
     "14",
     "8",
     "16",
     "18.9",
     "2",
     "—"
    ],
    [
     "68",
     "69",
     "70.5",
     "99",
     "14",
     "8",
     "16",
     "18.9",
     "2",
     "—"
    ],
    [
     "72",
     "73",
     "74.5",
     "103",
     "14",
     "8",
     "16",
     "18.9",
     "2",
     "—"
    ],
    [
     "80",
     "81",
     "82.5",
     "111",
     "14",
     "8",
     "16",
     "18.9",
     "2",
     "—"
    ],
    [
     "90",
     "91",
     "92.5",
     "121",
     "14",
     "8",
     "16",
     "18.9",
     "2",
     "—"
    ],
    [
     "100",
     "101",
     "102.5",
     "131",
     "14",
     "8",
     "16",
     "18.9",
     "2",
     "—"
    ]
   ]
  }
 },
 "sheet_text": "Spring lock washers, DIN 127 B (split washers, rectangular section): M2–M100 bore, outside diameter, width, thickness, free height — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/spring-lock-washers-din-127-b/  (sheet CC BY 4.0)\nBasis: Westfield Fasteners' DIN 127 table (type B, 2 to 100 mm), cross-checked on 15 sizes against McMaster-Carr's DIN 127B lock washer listing (ID, OD, thickness range); numbers only\nCatalog version: 2026-10-20\n\nSizes: see table below\n- DIN 127 B is the helical spring (split) lock washer with square ends and rectangular section. Columns (mm): d1 bore min and max; d2 outside max; b width of section; s thickness; h free height of type B, min and max; r as printed. Rows b and s are 19 values per table after the label cell: the page's own markup puts a dash in the label column (limit column), so the dash is not a value. McMaster-Carr's thickness ranges agree with s on all 15 sizes compared (e.g. M6 1.5 to 1.7 against s 1.6; M10 2.0 to 2.4 against s 2.2; M24 4.8 to 5.2 against s 5), and McMaster's ID / OD equal d1 max and d2 max for those sizes.\n- The last column shows McMaster-Carr's ID / OD / thickness range for the sizes it lists (M2, M2.5, M3, M4, M5, M6, M8, M10, M12, M16, M20, M24, M30, M36, M48). McMaster prints no width b. McMaster lists a few alternatives by finish (M3.5 3.9 or 3.6 mm bore in zinc steel; M27 27.5 or 28.5 mm) as printed there; Westfield's d1 for M27 is 27.5 min / 28.5 max, which explains the second value.\n- One printed anomaly dropped: Westfield's type B minimum free height for size 39 reads 2 (neighbours 12 and 14); it is shown as a typo and left out. Sizes above M24 are given by their nominal size only on the Westfield table (sizes 30 to 100 have no M prefix in the header).\n- Westfield's notes: DIN 127 applies to assemblies up to property class 5.8, reverse coil is recommended for left-hand threads, and type A (with prongs) is not tabulated here. The washer free height h is the coil height before tightening; the flat-state geometry (coil pitch, cut angle) is not given as numbers in the sources read, so no model is drawn.\n- McMaster-Carr sells DIN 127B lock washers with per-part STEP; its DIN 127B category is linked, not copied.\n\nsize  d1 min  d1 max  d2 max  b  s  h type B min  h type B max  r  McMaster ID / OD / thickness\nM2  2.1  2.4  4.4  0.9  0.5  1  1.2  0.1  2.4 / 4.4 / 0.4 to 0.6\nM2.2  2.3  2.6  4.8  1  0.6  1.2  1.4  0.1  —\nM2.5  2.6  2.9  5.1  1  0.6  1.2  1.4  0.1  2.9 / 5.1 / 0.5 to 0.7\nM3  3.1  3.4  6.2  1.3  0.8  1.6  1.9  0.2  3.4 / 6.2 / 0.7 to 0.9\nM3.5  3.6  3.9  6.7  1.3  0.8  1.6  1.9  0.2  —\nM4  4.1  4.4  7.6  1.5  0.9  1.8  2.1  0.2  4.4 / 7.6 / 0.8 to 1.0\nM5  5.1  5.4  9.2  1.8  1.2  2.4  2.8  0.2  5.4 / 9.2 / 1.1 to 1.3\nM6  6.1  6.5  11.8  2.5  1.6  3.2  3.8  0.3  6.5 / 11.8 / 1.5 to 1.7\nM7  7.1  7.5  12.8  2.5  1.6  3.2  3.8  0.3  —\nM8  8.1  8.5  14.8  3  2  4  4.7  0.5  8.5 / 14.8 / 1.9 to 2.1\nM10  10.2  10.7  18.1  3.5  2.2  4.4  5.2  0.5  10.7 / 18.1 / 2.0 to 2.4\nM12  12.2  12.7  21.1  4  2.5  5  5.9  1  12.7 / 21.1 / 2.3 to 2.7\nM14  14.2  14.7  24.1  4.5  3  6  7.1  1  —\nM16  16.2  17  27.4  5  3.5  7  8.3  1  17.0 / 27.4 / 3.3 to 3.7\nM18  18.2  19  29.4  5  3.5  7  8.3  1  —\nM20  20.2  21.2  33.6  6  4  8  9.4  1  21.2 / 33.6 / 3.8 to 4.2\nM22  22.5  23.5  35.9  6  4  8  9.4  1  —\nM24  24.5  25.5  40  7  5  10  11.8  1.6  25.5 / 40.0 / 4.8 to 5.2\nM27  27.5  28.5  43  7  5  10  11.8  1.6  —\nM30  30.5  31.7  48.2  8  6  12  14.2  1.6  31.7 / 48.2 / 5.8 to 6.2\nM36  36.5  37.7  58.2  10  6  12  14.2  1.6  37.7 / 58.2 / 5.8 to 6.2\nM39  39.5  40.7  61.2  10  6  — (printed 2; typo)  14.2  1.6  —\n42  42.5  43.7  68.2  12  7  14  16.5  2  —\n45  45.5  46.7  71.2  12  7  14  16.5  2  —\n48  49  50.5  75  12  7  14  16.5  2  50.5 / 75.0 / 6.8 to 7.2\n52  53  54.5  83  14  8  16  18.9  2  —\n56  57  58.5  87  14  8  16  18.9  2  —\n60  61  62.5  91  14  8  16  18.9  2  —\n64  65  66.5  95  14  8  16  18.9  2  —\n68  69  70.5  99  14  8  16  18.9  2  —\n72  73  74.5  103  14  8  16  18.9  2  —\n80  81  82.5  111  14  8  16  18.9  2  —\n90  91  92.5  121  14  8  16  18.9  2  —\n100  101  102.5  131  14  8  16  18.9  2  —\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Westfield Fasteners: Helical spring washers, DIN 127 B rectangular section: d1 min / max, d2 max, b, s, h (type B), r, 2 to 100 mm — web — Publisher's page; dimensions are facts — https://www.westfieldfasteners.co.uk/Standards/Washer-SprgRec-M.html\n- McMaster-Carr: DIN 127 B split lock washers (free STEP/IGES per part, for your own design use; no redistribution) — STEP, IGES, PDF — McMaster-Carr site terms: personal design use, no redistribution [verify license at link] — https://www.mcmaster.com/din-127b-lock-washers\n\nNo true-size file yet: the published figures do not fix the whole shape; a measured scan is planned.\nAPI: https://xemstudio.com/api/geometry?object=spring-lock-washers-din-127-b\n",
 "sources": [
  {
   "publisher": "Westfield Fasteners",
   "title": "Helical spring washers, DIN 127 B rectangular section: d1 min / max, d2 max, b, s, h (type B), r, 2 to 100 mm",
   "url": "https://www.westfieldfasteners.co.uk/Standards/Washer-SprgRec-M.html",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "McMaster-Carr",
   "title": "DIN 127 B split lock washers (free STEP/IGES per part, for your own design use; no redistribution)",
   "url": "https://www.mcmaster.com/din-127b-lock-washers",
   "formats": [
    "STEP",
    "IGES",
    "PDF"
   ],
   "license": "McMaster-Carr site terms: personal design use, no redistribution",
   "license_verified": false,
   "hosted": false
  }
 ],
 "xem": {
  "status": "not-scanned",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "flat-washers-metric",
  "flat-washers-metric-m10-m24",
  "serrated-lock-washers-din-6798",
  "large-washers-din-9021-iso-7093",
  "socket-head-cap-screws-metric"
 ],
 "fits": [],
 "dimensions": "exact (nominal, no tolerance added)",
 "dimension_rule": "All geometry on Xem Studio is exact (nominal, true size) with no tolerance added. Where a part meets another part, the object lists its mating features (feature, exact size, what it mates with, fit class: press, slide, run, socket, clamp or designed). Apply your process's allowance to those features only; 'designed' gaps are part of the design and stay as drawn. Typical accuracy by process and ISO 286 fits: https://xemstudio.com/tolerances/",
 "mating": [],
 "faq": [
  {
   "q": "What are the dimensions of an M8 DIN 127 B spring washer?",
   "a": "Bore 8.1 to 8.5 mm, outside diameter 14.8 mm max, width b 3, thickness s 2, free height 4 to 4.7 mm (Westfield); McMaster lists 8.5 ID, 14.8 OD, thickness 1.9 to 2.1."
  },
  {
   "q": "What is the outside diameter of an M10 split lock washer?",
   "a": "18.1 mm max (DIN 127 B, Westfield and McMaster agree); bore 10.2 to 10.7 mm, s 2.2."
  }
 ],
 "files_license": null,
 "offers": [],
 "markdown": "https://xemstudio.com/objects/spring-lock-washers-din-127-b/index.md"
}