{
 "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": "rubber-stoppers-and-corks",
 "name": "Laboratory rubber stoppers #0–#13 and wine corks",
 "kind": "standard",
 "category": "Hardware",
 "group": "Found & household materials",
 "year": null,
 "question": "What size rubber stopper fits a 25 mm test tube or a soda bottle?",
 "tags": [
  "stopper",
  "cork",
  "bung",
  "seal",
  "lab",
  "stirling",
  "long earth society",
  "found materials"
 ],
 "aliases": [
  "rubber stopper sizes",
  "stopper size chart",
  "#6 stopper dimensions",
  "wine cork size",
  "test tube stopper size",
  "bung sizes"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": true,
 "free_files": 17,
 "url": "https://xemstudio.com/objects/rubber-stoppers-and-corks/",
 "sheet_txt": "https://xemstudio.com/objects/rubber-stoppers-and-corks/sheet.txt",
 "sheet": {
  "basis": "Standard US laboratory stopper sizes (top and bottom diameters, 25 mm tall, taper ~1:8); wine corks #9 (Ø24 × 44/49)",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "Stopper number → top/bottom diameter (mm): #0 17/13, #1 19/15, #2 20/16, #3 24/18, #4 26/20, #5 27/23, #6 32/26, #6½ 34/27, #7 37/30, #8 41/33, #9 45/37, #10 50/42, #11 56/48, #12 64/54, #13 68/58. All 25 mm tall; one- and two-hole versions take 5–7 mm glass tube.",
   "Pick the stopper whose mid-diameter is 1 mm over the opening: 16 mm test tube → #0; 20 mm → #2; 25 mm → #4/#5; 28 mm soda-bottle neck → #6; 70 mm jar mouth → #13 is too small, use a printed disc.",
   "Corks: #9 natural wine cork Ø24 × 44 mm (49 long for aged wines), compressible to Ø21; silicone stoppers survive 230 °C, natural rubber 80 °C. A cork drilled 3 mm is the cheapest displacer-rod gland for a test-tube engine."
  ],
  "table": {
   "columns": [
    "number",
    "top_mm",
    "bottom_mm",
    "height_mm",
    "fits_opening_mm"
   ],
   "rows": [
    [
     "#0",
     17,
     13,
     25,
     "14–16"
    ],
    [
     "#1",
     19,
     15,
     25,
     "16–18"
    ],
    [
     "#2",
     20,
     16,
     25,
     "17–19"
    ],
    [
     "#3",
     24,
     18,
     25,
     "19–23"
    ],
    [
     "#4",
     26,
     20,
     25,
     "21–25"
    ],
    [
     "#5",
     27,
     23,
     25,
     "24–26"
    ],
    [
     "#6",
     32,
     26,
     25,
     "27–31"
    ],
    [
     "#6.5",
     34,
     27,
     25,
     "28–33"
    ],
    [
     "#7",
     37,
     30,
     25,
     "31–36"
    ],
    [
     "#8",
     41,
     33,
     25,
     "34–40"
    ],
    [
     "#9",
     45,
     37,
     25,
     "38–44"
    ],
    [
     "#10",
     50,
     42,
     25,
     "43–49"
    ],
    [
     "#11",
     56,
     48,
     25,
     "49–55"
    ],
    [
     "#12",
     64,
     54,
     25,
     "55–63"
    ],
    [
     "#13",
     68,
     58,
     25,
     "59–67"
    ],
    [
     "#9 cork",
     24,
     24,
     "44 / 49",
     "22–23"
    ]
   ]
  }
 },
 "sheet_text": "Laboratory rubber stoppers #0–#13 and wine corks — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/rubber-stoppers-and-corks/  (CC BY 4.0)\nBasis: Standard US laboratory stopper sizes (top and bottom diameters, 25 mm tall, taper ~1:8); wine corks #9 (Ø24 × 44/49)\nCatalog version: 2026-10-20\n\nSizes: see table below\n- Stopper number → top/bottom diameter (mm): #0 17/13, #1 19/15, #2 20/16, #3 24/18, #4 26/20, #5 27/23, #6 32/26, #6½ 34/27, #7 37/30, #8 41/33, #9 45/37, #10 50/42, #11 56/48, #12 64/54, #13 68/58. All 25 mm tall; one- and two-hole versions take 5–7 mm glass tube.\n- Pick the stopper whose mid-diameter is 1 mm over the opening: 16 mm test tube → #0; 20 mm → #2; 25 mm → #4/#5; 28 mm soda-bottle neck → #6; 70 mm jar mouth → #13 is too small, use a printed disc.\n- Corks: #9 natural wine cork Ø24 × 44 mm (49 long for aged wines), compressible to Ø21; silicone stoppers survive 230 °C, natural rubber 80 °C. A cork drilled 3 mm is the cheapest displacer-rod gland for a test-tube engine.\n\nnumber  top_mm  bottom_mm  height_mm  fits_opening_mm\n#0  17  13  25  14–16\n#1  19  15  25  16–18\n#2  20  16  25  17–19\n#3  24  18  25  19–23\n#4  26  20  25  21–25\n#5  27  23  25  24–26\n#6  32  26  25  27–31\n#6.5  34  27  25  28–33\n#7  37  30  25  31–36\n#8  41  33  25  34–40\n#9  45  37  25  38–44\n#10  50  42  25  43–49\n#11  56  48  25  49–55\n#12  64  54  25  55–63\n#13  68  58  25  59–67\n#9 cork  24  24  44 / 49  22–23\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Wikipedia: Bung — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Bung\n- Wikipedia: Cork (material) — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Cork_(material)\n- Long Earth Society: Engine builds (videos and write-ups) — web, video — LES site — https://longearthsociety.com/engineering/\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 17 parts): https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/index.json\nAPI: https://xemstudio.com/api/geometry?object=rubber-stoppers-and-corks\n",
 "sources": [
  {
   "publisher": "Wikipedia",
   "title": "Bung",
   "url": "https://en.wikipedia.org/wiki/Bung",
   "formats": [
    "web"
   ],
   "license": "CC BY-SA 4.0 (text)",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Wikipedia",
   "title": "Cork (material)",
   "url": "https://en.wikipedia.org/wiki/Cork_(material)",
   "formats": [
    "web"
   ],
   "license": "CC BY-SA 4.0 (text)",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Long Earth Society",
   "title": "Engine builds (videos and write-ups)",
   "url": "https://longearthsociety.com/engineering/",
   "formats": [
    "web",
    "video"
   ],
   "license": "LES site",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "borosilicate-test-tubes",
  "mason-jars-and-lids",
  "pet-bottle-necks-pco1881",
  "brass-tube-ks"
 ],
 "faq": [
  {
   "q": "What rubber stopper fits a 20 mm test tube?",
   "a": "#2 (20 mm top, 16 mm bottom); a #1 for 16–18 mm tubes, #4 for a 25 mm tube."
  },
  {
   "q": "What size is a wine cork?",
   "a": "#9: 24 mm diameter, 44 mm long (49 mm for long corks); it compresses to 21–22 mm in the bottle neck."
  },
  {
   "q": "Which stopper fits a soda bottle neck?",
   "a": "#6 (32/26 mm) for the 28 mm PCO 1881 neck; #7 for a 38 mm juice neck."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "stopper-0",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-0.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-0.stl",
   "note": "#0 stopper: Ø17 top, Ø13 bottom, 25 mm tall"
  },
  {
   "file": "stopper-1",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-1.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-1.stl",
   "note": "#1 stopper: Ø19 top, Ø15 bottom, 25 mm tall"
  },
  {
   "file": "stopper-2",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-2.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-2.stl",
   "note": "#2 stopper: Ø20 top, Ø16 bottom, 25 mm tall"
  },
  {
   "file": "stopper-3",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-3.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-3.stl",
   "note": "#3 stopper: Ø24 top, Ø18 bottom, 25 mm tall"
  },
  {
   "file": "stopper-4",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-4.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-4.stl",
   "note": "#4 stopper: Ø26 top, Ø20 bottom, 25 mm tall"
  },
  {
   "file": "stopper-5",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-5.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-5.stl",
   "note": "#5 stopper: Ø27 top, Ø23 bottom, 25 mm tall"
  },
  {
   "file": "stopper-6",
   "formats": [
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    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-6.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-6.stl",
   "note": "#6 stopper: Ø32 top, Ø26 bottom, 25 mm tall"
  },
  {
   "file": "stopper-6-5",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-6-5.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-6-5.stl",
   "note": "#6.5 stopper: Ø34 top, Ø27 bottom, 25 mm tall"
  },
  {
   "file": "stopper-7",
   "formats": [
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    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-7.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-7.stl",
   "note": "#7 stopper: Ø37 top, Ø30 bottom, 25 mm tall"
  },
  {
   "file": "stopper-8",
   "formats": [
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    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-8.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-8.stl",
   "note": "#8 stopper: Ø41 top, Ø33 bottom, 25 mm tall"
  },
  {
   "file": "stopper-9",
   "formats": [
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   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-9.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-9.stl",
   "note": "#9 stopper: Ø45 top, Ø37 bottom, 25 mm tall"
  },
  {
   "file": "stopper-10",
   "formats": [
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    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-10.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-10.stl",
   "note": "#10 stopper: Ø50 top, Ø42 bottom, 25 mm tall"
  },
  {
   "file": "stopper-11",
   "formats": [
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    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-11.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-11.stl",
   "note": "#11 stopper: Ø56 top, Ø48 bottom, 25 mm tall"
  },
  {
   "file": "stopper-12",
   "formats": [
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    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-12.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-12.stl",
   "note": "#12 stopper: Ø64 top, Ø54 bottom, 25 mm tall"
  },
  {
   "file": "stopper-13",
   "formats": [
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    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-13.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/stopper-13.stl",
   "note": "#13 stopper: Ø68 top, Ø58 bottom, 25 mm tall"
  },
  {
   "file": "cork-9-wine",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/cork-9-wine.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/cork-9-wine.stl",
   "note": "#9 wine cork Ø24 × 44 (natural)"
  },
  {
   "file": "cork-9-wine-49",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/cork-9-wine-49.step",
   "stl": "https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/cork-9-wine-49.stl",
   "note": "#9 wine cork Ø24 × 49 (long)"
  }
 ],
 "markdown": "https://xemstudio.com/objects/rubber-stoppers-and-corks/index.md"
}