{
 "version": "2026-10-20",
 "license": "Dimension sheets are written by Xem Studio from the cited sources and are free to use (CC BY 4.0, attribute 'Xem Studio'). Linked files belong to their publishers under the license shown; Xem Studio does not host them. 'license_verified: false' means the license shown is from memory or the publisher's page as last read and should be confirmed at the link before commercial use.",
 "slug": "flat-washers-inch",
 "name": "Flat washers, inch: SAE and USS, 1/4 to 3/4 in (ASME B18.21.1 Type A)",
 "kind": "standard",
 "category": "Hardware",
 "group": "Fasteners",
 "year": null,
 "question": "What is the difference between SAE and USS washers?",
 "tags": [
  "washer",
  "sae",
  "uss"
 ],
 "aliases": [
  "sae vs uss washer",
  "5/16 washer dimensions",
  "inch flat washer step"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 14,
 "url": "https://xemstudio.com/objects/flat-washers-inch/",
 "sheet_txt": "https://xemstudio.com/objects/flat-washers-inch/sheet.txt",
 "sheet": {
  "basis": "ASME B18.21.1 Type A plain washers, narrow (SAE) and wide (USS): ID, OD, thickness (nominal)",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "SAE washers are narrow (fit under socket heads and in tight spots); USS are wide (spread load on wood and soft material)."
  ],
  "table": {
   "columns": [
    "size",
    "type",
    "id_in",
    "od_in",
    "thickness_in"
   ],
   "rows": [
    [
     "1/4",
     "USS",
     0.312,
     0.734,
     0.065
    ],
    [
     "1/4",
     "SAE",
     0.281,
     0.625,
     0.065
    ],
    [
     "5/16",
     "USS",
     0.375,
     0.875,
     0.083
    ],
    [
     "5/16",
     "SAE",
     0.344,
     0.688,
     0.065
    ],
    [
     "3/8",
     "USS",
     0.438,
     1,
     0.083
    ],
    [
     "3/8",
     "SAE",
     0.406,
     0.812,
     0.065
    ],
    [
     "7/16",
     "USS",
     0.5,
     1.25,
     0.083
    ],
    [
     "7/16",
     "SAE",
     0.469,
     0.922,
     0.065
    ],
    [
     "1/2",
     "USS",
     0.562,
     1.375,
     0.109
    ],
    [
     "1/2",
     "SAE",
     0.531,
     1.062,
     0.095
    ],
    [
     "5/8",
     "USS",
     0.688,
     1.75,
     0.134
    ],
    [
     "5/8",
     "SAE",
     0.656,
     1.312,
     0.095
    ],
    [
     "3/4",
     "USS",
     0.812,
     2,
     0.148
    ],
    [
     "3/4",
     "SAE",
     0.812,
     1.469,
     0.134
    ]
   ]
  }
 },
 "sheet_text": "Flat washers, inch: SAE and USS, 1/4 to 3/4 in (ASME B18.21.1 Type A) — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/flat-washers-inch/  (CC BY 4.0)\nBasis: ASME B18.21.1 Type A plain washers, narrow (SAE) and wide (USS): ID, OD, thickness (nominal)\nCatalog version: 2026-10-20\n\nSizes: see table below\n- SAE washers are narrow (fit under socket heads and in tight spots); USS are wide (spread load on wood and soft material).\n\nsize  type  id_in  od_in  thickness_in\n1/4  USS  0.312  0.734  0.065\n1/4  SAE  0.281  0.625  0.065\n5/16  USS  0.375  0.875  0.083\n5/16  SAE  0.344  0.688  0.065\n3/8  USS  0.438  1.0  0.083\n3/8  SAE  0.406  0.812  0.065\n7/16  USS  0.5  1.25  0.083\n7/16  SAE  0.469  0.922  0.065\n1/2  USS  0.562  1.375  0.109\n1/2  SAE  0.531  1.062  0.095\n5/8  USS  0.688  1.75  0.134\n5/8  SAE  0.656  1.312  0.095\n3/4  USS  0.812  2.0  0.148\n3/4  SAE  0.812  1.469  0.134\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- ASME: ASME B18.21.1 Washers: helical spring-lock, tooth lock, and plain washers (inch) — standard — ASME; dimensions are facts [verify license at link] — https://www.asme.org/codes-standards/find-codes-standards/b18-21-1-washers-helical-spring-lock-tooth-lock-plain-washers-(inch-series)\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 14 parts): https://xemstudio.com/files/hardware/flat-washers-inch/index.json\nAPI: https://xemstudio.com/api/geometry?object=flat-washers-inch\n",
 "sources": [
  {
   "publisher": "ASME",
   "title": "ASME B18.21.1 Washers: helical spring-lock, tooth lock, and plain washers (inch)",
   "url": "https://www.asme.org/codes-standards/find-codes-standards/b18-21-1-washers-helical-spring-lock-tooth-lock-plain-washers-(inch-series)",
   "formats": [
    "standard"
   ],
   "license": "ASME; dimensions are facts",
   "license_verified": false,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "hex-bolts-inch",
  "hex-nuts-inch",
  "socket-head-cap-screws-inch",
  "button-head-socket-screws-inch",
  "imperial-machine-screws"
 ],
 "fits": [],
 "dimensions": "exact (nominal, no printing tolerance)",
 "dimension_rule": "All geometry on Xem Studio is exact (nominal, true size) with no printing tolerance. 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.",
 "mating": [],
 "faq": [
  {
   "q": "SAE or USS?",
   "a": "SAE for metal and tight spaces, USS for wood and soft material."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "washer-uss-1-4-20",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-1-4-20.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-1-4-20.stl",
   "note": "1/4 in USS flat washer: 0.312 × 0.734 × 0.065 in"
  },
  {
   "file": "washer-sae-1-4-20",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-1-4-20.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-1-4-20.stl",
   "note": "1/4 in SAE flat washer: 0.281 × 0.625 × 0.065 in"
  },
  {
   "file": "washer-uss-5-16-18",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-5-16-18.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-5-16-18.stl",
   "note": "5/16 in USS flat washer: 0.375 × 0.875 × 0.083 in"
  },
  {
   "file": "washer-sae-5-16-18",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-5-16-18.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-5-16-18.stl",
   "note": "5/16 in SAE flat washer: 0.344 × 0.688 × 0.065 in"
  },
  {
   "file": "washer-uss-3-8-16",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-3-8-16.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-3-8-16.stl",
   "note": "3/8 in USS flat washer: 0.438 × 1.000 × 0.083 in"
  },
  {
   "file": "washer-sae-3-8-16",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-3-8-16.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-3-8-16.stl",
   "note": "3/8 in SAE flat washer: 0.406 × 0.812 × 0.065 in"
  },
  {
   "file": "washer-uss-7-16-14",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-7-16-14.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-7-16-14.stl",
   "note": "7/16 in USS flat washer: 0.500 × 1.250 × 0.083 in"
  },
  {
   "file": "washer-sae-7-16-14",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-7-16-14.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-7-16-14.stl",
   "note": "7/16 in SAE flat washer: 0.469 × 0.922 × 0.065 in"
  },
  {
   "file": "washer-uss-1-2-13",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-1-2-13.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-1-2-13.stl",
   "note": "1/2 in USS flat washer: 0.562 × 1.375 × 0.109 in"
  },
  {
   "file": "washer-sae-1-2-13",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-1-2-13.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-1-2-13.stl",
   "note": "1/2 in SAE flat washer: 0.531 × 1.062 × 0.095 in"
  },
  {
   "file": "washer-uss-5-8-11",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-5-8-11.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-5-8-11.stl",
   "note": "5/8 in USS flat washer: 0.688 × 1.750 × 0.134 in"
  },
  {
   "file": "washer-sae-5-8-11",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-5-8-11.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-5-8-11.stl",
   "note": "5/8 in SAE flat washer: 0.656 × 1.312 × 0.095 in"
  },
  {
   "file": "washer-uss-3-4-10",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-3-4-10.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-uss-3-4-10.stl",
   "note": "3/4 in USS flat washer: 0.812 × 2.000 × 0.148 in"
  },
  {
   "file": "washer-sae-3-4-10",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-3-4-10.step",
   "stl": "https://xemstudio.com/files/hardware/flat-washers-inch/washer-sae-3-4-10.stl",
   "note": "3/4 in SAE flat washer: 0.812 × 1.469 × 0.134 in"
  }
 ],
 "markdown": "https://xemstudio.com/objects/flat-washers-inch/index.md"
}