{
 "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": "push-to-connect-fitting-sizes",
 "name": "Push-to-connect pneumatic fittings: tube OD 4 to 12 mm and 1/8 to 1/2 in with the thread sizes offered",
 "kind": "standard",
 "category": "Tri-clamp & pipe",
 "group": "Pipe, tube & threads",
 "year": null,
 "question": "Which tube sizes and thread sizes do push-to-connect fittings come in?",
 "tags": [
  "push-in",
  "pneumatic",
  "fitting",
  "tube",
  "air",
  "thread"
 ],
 "aliases": [
  "push to connect fitting sizes",
  "push in fitting sizes",
  "pneumatic fitting thread",
  "kq2h sizes",
  "6mm to 1/4 npt",
  "air line fitting tube od",
  "one touch fitting sizes"
 ],
 "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/push-to-connect-fitting-sizes/",
 "sheet_txt": "https://xemstudio.com/objects/push-to-connect-fitting-sizes/sheet.txt",
 "sheet": {
  "basis": "SMC KQ2H male connector series listings (metric and NPT inch ranges); numbers only",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "Push-to-connect (push-in, one-touch) fittings take tube by outside diameter: metric 4, 6, 8, 10, 12 (and 16) mm, inch 1/8, 5/32, 1/4, 5/16, 3/8, 1/2 in. The table lists the male threads SMC offers on its straight male connector KQ2H for each tube OD (metric: tapered R, ISO 7, or M5/M6; inch: NPT). A tube must match the OD to within the maker's tube tolerance; soft PU/nylon tubes in the same nominal OD are not interchangeable with hard ones.",
   "Tube dimensions (OD, ID, wall) of PU tube are on the PU pneumatic tube page. 5/32 in is 3.97 mm, 1/4 in is 6.35 mm, 3/8 in is 9.53 mm: metric and inch tubes of similar size do not interchange (6 mm vs 1/4 in leaks or blows out).",
   "Left out, no file: collet and cartridge bore, hex size and body length are in SMC's PDF catalogue (not readable here) and Festo/Legris tables were not checked; retail pages do not print them, so we publish no body."
  ],
  "table": {
   "columns": [
    "tube OD",
    "male threads offered (SMC KQ2H)"
   ],
   "rows": [
    [
     "4 mm",
     "R1/8, R1/4, M5, M6"
    ],
    [
     "6 mm",
     "R1/8, R1/4, R3/8, M5, M6"
    ],
    [
     "8 mm",
     "R1/8, R1/4, R3/8"
    ],
    [
     "10 mm",
     "R1/8, R1/4, R3/8, R1/2"
    ],
    [
     "12 mm",
     "R1/4, R3/8, R1/2"
    ],
    [
     "16 mm",
     "R3/8, R1/2"
    ],
    [
     "1/8 in",
     "NPT 1/16, 1/8, 1/4"
    ],
    [
     "5/32 in",
     "NPT 1/16, 1/8, 1/4"
    ],
    [
     "1/4 in",
     "NPT 1/16, 1/8, 1/4, 3/8"
    ],
    [
     "5/16 in",
     "NPT 1/8, 1/4, 3/8"
    ],
    [
     "3/8 in",
     "NPT 1/8, 1/4, 3/8, 1/2"
    ],
    [
     "1/2 in",
     "NPT 1/4, 3/8, 1/2"
    ]
   ]
  }
 },
 "sheet_text": "Push-to-connect pneumatic fittings: tube OD 4 to 12 mm and 1/8 to 1/2 in with the thread sizes offered — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/push-to-connect-fitting-sizes/  (sheet CC BY 4.0)\nBasis: SMC KQ2H male connector series listings (metric and NPT inch ranges); numbers only\nCatalog version: 2026-10-20\n\nSizes: see table below\n- Push-to-connect (push-in, one-touch) fittings take tube by outside diameter: metric 4, 6, 8, 10, 12 (and 16) mm, inch 1/8, 5/32, 1/4, 5/16, 3/8, 1/2 in. The table lists the male threads SMC offers on its straight male connector KQ2H for each tube OD (metric: tapered R, ISO 7, or M5/M6; inch: NPT). A tube must match the OD to within the maker's tube tolerance; soft PU/nylon tubes in the same nominal OD are not interchangeable with hard ones.\n- Tube dimensions (OD, ID, wall) of PU tube are on the PU pneumatic tube page. 5/32 in is 3.97 mm, 1/4 in is 6.35 mm, 3/8 in is 9.53 mm: metric and inch tubes of similar size do not interchange (6 mm vs 1/4 in leaks or blows out).\n- Left out, no file: collet and cartridge bore, hex size and body length are in SMC's PDF catalogue (not readable here) and Festo/Legris tables were not checked; retail pages do not print them, so we publish no body.\n\ntube OD  male threads offered (SMC KQ2H)\n4 mm  R1/8, R1/4, M5, M6\n6 mm  R1/8, R1/4, R3/8, M5, M6\n8 mm  R1/8, R1/4, R3/8\n10 mm  R1/8, R1/4, R3/8, R1/2\n12 mm  R1/4, R3/8, R1/2\n16 mm  R3/8, R1/2\n1/8 in  NPT 1/16, 1/8, 1/4\n5/32 in  NPT 1/16, 1/8, 1/4\n1/4 in  NPT 1/16, 1/8, 1/4, 3/8\n5/16 in  NPT 1/8, 1/4, 3/8\n3/8 in  NPT 1/8, 1/4, 3/8, 1/2\n1/2 in  NPT 1/4, 3/8, 1/2\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- SMC Pneumatics (distributor): KQ2H male connector, metric — web — Publisher's page; dimensions are facts — https://www.smcpneumatics.com/mkq2h.html\n- SMC Pneumatics (distributor): KQ2H male connector, inch tube, NPT — web — Publisher's page; dimensions are facts — https://www.smcpneumatics.com/newKQ2Hnpt.html\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=push-to-connect-fitting-sizes\n",
 "sources": [
  {
   "publisher": "SMC Pneumatics (distributor)",
   "title": "KQ2H male connector, metric",
   "url": "https://www.smcpneumatics.com/mkq2h.html",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "SMC Pneumatics (distributor)",
   "title": "KQ2H male connector, inch tube, NPT",
   "url": "https://www.smcpneumatics.com/newKQ2Hnpt.html",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "not-scanned",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "pu-pneumatic-tube",
  "push-fit-fittings",
  "npt-thread-envelopes",
  "bsp-thread-envelopes",
  "hose-barbs"
 ],
 "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": "Does 1/4 in tube fit a 6 mm push-in fitting?",
   "a": "No: 1/4 in is 6.35 mm. It does not seal reliably in a 6 mm fitting; use the matching inch fitting."
  },
  {
   "q": "What threads come on 6 mm push-in male connectors?",
   "a": "SMC KQ2H 6 mm: R1/8, R1/4, R3/8, M5 and M6."
  }
 ],
 "files_license": null,
 "offers": [],
 "markdown": "https://xemstudio.com/objects/push-to-connect-fitting-sizes/index.md"
}