{
 "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": "air-quick-coupler-plug-profiles",
 "name": "Air quick-coupler plug profiles: industrial M / H / G, Tru-Flate T, ARO A, European 7.2, Japanese, Lincoln, Schrader (tip diameter and length)",
 "kind": "standard",
 "category": "Tri-clamp & pipe",
 "group": "Pipe, tube & threads",
 "year": null,
 "question": "Which air coupler plug is which: how big are the tips of industrial (Milton M-style), Tru-Flate (T-style), ARO (A-style) and European plugs, and do they interchange?",
 "tags": [
  "air coupler",
  "quick coupler",
  "quick disconnect",
  "air fitting",
  "compressor",
  "plug",
  "industrial interchange",
  "tru-flate",
  "aro",
  "milton",
  "pneumatic",
  "tool"
 ],
 "aliases": [
  "air coupler sizes",
  "milton m style plug dimensions",
  "t style vs m style air coupler",
  "a style air coupler aro 210",
  "tru flate coupler dimensions",
  "industrial vs automotive air coupler",
  "air plug tip diameter",
  "iso 6150 b plug",
  "european 7.2 air coupler",
  "1/4 industrial air coupler dimensions",
  "milton h style 3/8 plug",
  "air coupler profile chart",
  "aro 210 plug size",
  "air chuck plug profiles",
  "g style air coupler 1/2"
 ],
 "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/air-quick-coupler-plug-profiles/",
 "sheet_txt": "https://xemstudio.com/objects/air-quick-coupler-plug-profiles/sheet.txt",
 "sheet": {
  "basis": "Park Tool's published tip diameter (A) and tip length (B) table for each plug profile, with naming and standards from Wikipedia, Milton distributor listings, Guardair and Prevost; numbers only",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "Plug profiles are distinguished by the tip (the nose that enters the coupler): tip diameter A and tip length B, as Park Tool names them. Two plugs with the same tip diameter are NOT interchangeable if the tip length differs: 1/4 in industrial (M) is 5/16 in × 3/16 in (7.94 × 4.76 mm); 1/4 in ARO (A) is also 5/16 in diameter but 5/16 in (NPT) or 3/8 in (BSPT) long; 1/4 in Tru-Flate (T) is 3/8 in × 1/16 in; 1/4 in European is 3/8 in × 3/16 in. The 'flow size' is the plug and coupler body size (1/4, 3/8 ...), not the thread on the back of the plug.",
   "Naming. Park Tool uses the Milton letters: M-style (1/4), H-style (3/8), G-style (1/2) for the industrial profile; A-style for ARO; V-style for European. Guardair calls the industrial profile 'Industrial Interchange, also M-style, I/M-style, Type-D' and the European one 'High Flow: V-style, Megaflow, European interchange'. A Milton A-style plug is sold as interchanging with ARO 210 and a Milton T-style plug as interchanging with the Tru-Flate / Parker series (Hi-Line listings). Park Tool and the Hi-Line listing label the Tru-Flate series differently (Park Tool 'automotive'; Hi-Line 'Tru-Flate / Parker industrial interchange series'), so the T-style name is what to match, not the word automotive or industrial.",
   "Standards (Wikipedia, Air-line fitting): the US industrial 1/4 in (M) profile is listed under A-A-59439, ANSI T3.20.14-1990, MIL-C-4109F and ISO 6150 B, and ISO 6150 B is cited for the US industrial 1/4, 3/8 and 1/2 in profiles; ARO 210 is DN 5.5 and ARO 310 DN 9; the European 7.2 is DN 7.2/7.4 and Eurostandard 10 DN 10; no standard is listed there for the T or A profiles. Prevost's ISO 6150 B safety couplings (ISI 06) have a 6 mm passage and G1/4, G3/8, G1/2 male thread bodies (A 76.3 / 78.3 / 82.3 mm, B 30 mm, C 20 / 23 / 26 mm on the datasheet; the letters are not defined in the text read). The ISO 6150 B plug drawing and the size designations such as B-12 are not in a document we could read, so no ISO plug dimensions are listed.",
   "Single source for the numbers: Park Tool's table is the only document read that prints tip diameter and length (inch, with the mm it prints); no second maker table was found, so treat the figures as a guide to telling profiles apart, and measure a plug with calipers before ordering the other half. The mm values here are the inch value × 25.4 rounded to 2 decimals; Park Tool's own mm figures are within 0.03 mm of them.",
   "Not published as numbers in anything read: the groove, shoulder and sleeve geometry, the thread on the back (typically 1/4 or 3/8 NPT, but varies by part) and plug body diameter. No file is drawn. McMaster-Carr sells quick-disconnect plugs and sockets, including ARO style, with per-part STEP; its air-coupling pages are linked, not copied.",
   "Related: camlock (cam and groove) couplings for liquids and bulk hose: camlock-couplings. Push-to-connect tube fittings for pneumatics: push-to-connect-fitting-sizes."
  ],
  "table": {
   "columns": [
    "profile (Milton letter)",
    "flow size",
    "tip diameter A",
    "tip length B"
   ],
   "rows": [
    [
     "Industrial",
     "1/8 in",
     "1/4 in (6.35 mm)",
     "1/8 in (3.17 mm)"
    ],
    [
     "Industrial (Milton M-style)",
     "1/4 in",
     "5/16 in (7.94 mm)",
     "3/16 in (4.76 mm)"
    ],
    [
     "Industrial (Milton H-style)",
     "3/8 in",
     "7/16 in (11.11 mm)",
     "5/16 in (7.94 mm)"
    ],
    [
     "Industrial (Milton G-style)",
     "1/2 in",
     "9/16 in (14.29 mm)",
     "3/8 in (9.52 mm)"
    ],
    [
     "Industrial",
     "3/4 in",
     "13/16 in (20.64 mm)",
     "5/16 in (7.94 mm)"
    ],
    [
     "Tru-Flate (Milton T-style, automotive)",
     "1/4 in",
     "3/8 in (9.52 mm)",
     "1/16 in (1.59 mm)"
    ],
    [
     "Tru-Flate (automotive)",
     "3/8 in",
     "7/16 in (11.11 mm)",
     "1/8 in (3.17 mm)"
    ],
    [
     "Tru-Flate (automotive)",
     "1/2 in",
     "9/16 in (14.29 mm)",
     "1/8 in (3.17 mm)"
    ],
    [
     "ARO (Milton A-style), NPT",
     "1/4 in",
     "5/16 in (7.94 mm)",
     "5/16 in (7.94 mm)"
    ],
    [
     "ARO (Milton A-style), BSPT",
     "1/4 in",
     "5/16 in (7.94 mm)",
     "3/8 in (9.52 mm)"
    ],
    [
     "ARO (Milton A-style), NPT",
     "3/8 in",
     "7/16 in (11.11 mm)",
     "9/16 in (14.29 mm)"
    ],
    [
     "European (Milton V-style, Megaflow, NT 7.2 / DIN 7.2)",
     "1/4 in",
     "3/8 in (9.52 mm)",
     "3/16 in (4.76 mm)"
    ],
    [
     "Japanese",
     "1/4 in",
     "7/16 in (11.11 mm)",
     "7/32 in (5.56 mm)"
    ],
    [
     "Silverline bayonet (UK)",
     "3/16 in",
     "5/16 in (7.94 mm)",
     "11/32 in (8.73 mm)"
    ],
    [
     "Lincoln",
     "1/4 in",
     "9/32 in (7.14 mm)",
     "3/4 in (19.05 mm)"
    ],
    [
     "Schrader quick-connect (twist lock)",
     "1/4 in",
     "5/16 in (7.94 mm)",
     "3/4 in (19.05 mm)"
    ],
    [
     "Schrader quick-connect (twist lock)",
     "1/2 in",
     "1/2 in (12.7 mm)",
     "7/8 in (22.22 mm)"
    ]
   ]
  }
 },
 "sheet_text": "Air quick-coupler plug profiles: industrial M / H / G, Tru-Flate T, ARO A, European 7.2, Japanese, Lincoln, Schrader (tip diameter and length) — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/air-quick-coupler-plug-profiles/  (sheet CC BY 4.0)\nBasis: Park Tool's published tip diameter (A) and tip length (B) table for each plug profile, with naming and standards from Wikipedia, Milton distributor listings, Guardair and Prevost; numbers only\nCatalog version: 2026-10-20\n\nSizes: see table below\n- Plug profiles are distinguished by the tip (the nose that enters the coupler): tip diameter A and tip length B, as Park Tool names them. Two plugs with the same tip diameter are NOT interchangeable if the tip length differs: 1/4 in industrial (M) is 5/16 in × 3/16 in (7.94 × 4.76 mm); 1/4 in ARO (A) is also 5/16 in diameter but 5/16 in (NPT) or 3/8 in (BSPT) long; 1/4 in Tru-Flate (T) is 3/8 in × 1/16 in; 1/4 in European is 3/8 in × 3/16 in. The 'flow size' is the plug and coupler body size (1/4, 3/8 ...), not the thread on the back of the plug.\n- Naming. Park Tool uses the Milton letters: M-style (1/4), H-style (3/8), G-style (1/2) for the industrial profile; A-style for ARO; V-style for European. Guardair calls the industrial profile 'Industrial Interchange, also M-style, I/M-style, Type-D' and the European one 'High Flow: V-style, Megaflow, European interchange'. A Milton A-style plug is sold as interchanging with ARO 210 and a Milton T-style plug as interchanging with the Tru-Flate / Parker series (Hi-Line listings). Park Tool and the Hi-Line listing label the Tru-Flate series differently (Park Tool 'automotive'; Hi-Line 'Tru-Flate / Parker industrial interchange series'), so the T-style name is what to match, not the word automotive or industrial.\n- Standards (Wikipedia, Air-line fitting): the US industrial 1/4 in (M) profile is listed under A-A-59439, ANSI T3.20.14-1990, MIL-C-4109F and ISO 6150 B, and ISO 6150 B is cited for the US industrial 1/4, 3/8 and 1/2 in profiles; ARO 210 is DN 5.5 and ARO 310 DN 9; the European 7.2 is DN 7.2/7.4 and Eurostandard 10 DN 10; no standard is listed there for the T or A profiles. Prevost's ISO 6150 B safety couplings (ISI 06) have a 6 mm passage and G1/4, G3/8, G1/2 male thread bodies (A 76.3 / 78.3 / 82.3 mm, B 30 mm, C 20 / 23 / 26 mm on the datasheet; the letters are not defined in the text read). The ISO 6150 B plug drawing and the size designations such as B-12 are not in a document we could read, so no ISO plug dimensions are listed.\n- Single source for the numbers: Park Tool's table is the only document read that prints tip diameter and length (inch, with the mm it prints); no second maker table was found, so treat the figures as a guide to telling profiles apart, and measure a plug with calipers before ordering the other half. The mm values here are the inch value × 25.4 rounded to 2 decimals; Park Tool's own mm figures are within 0.03 mm of them.\n- Not published as numbers in anything read: the groove, shoulder and sleeve geometry, the thread on the back (typically 1/4 or 3/8 NPT, but varies by part) and plug body diameter. No file is drawn. McMaster-Carr sells quick-disconnect plugs and sockets, including ARO style, with per-part STEP; its air-coupling pages are linked, not copied.\n- Related: camlock (cam and groove) couplings for liquids and bulk hose: camlock-couplings. Push-to-connect tube fittings for pneumatics: push-to-connect-fitting-sizes.\n\nprofile (Milton letter)  flow size  tip diameter A  tip length B\nIndustrial  1/8 in  1/4 in (6.35 mm)  1/8 in (3.17 mm)\nIndustrial (Milton M-style)  1/4 in  5/16 in (7.94 mm)  3/16 in (4.76 mm)\nIndustrial (Milton H-style)  3/8 in  7/16 in (11.11 mm)  5/16 in (7.94 mm)\nIndustrial (Milton G-style)  1/2 in  9/16 in (14.29 mm)  3/8 in (9.52 mm)\nIndustrial  3/4 in  13/16 in (20.64 mm)  5/16 in (7.94 mm)\nTru-Flate (Milton T-style, automotive)  1/4 in  3/8 in (9.52 mm)  1/16 in (1.59 mm)\nTru-Flate (automotive)  3/8 in  7/16 in (11.11 mm)  1/8 in (3.17 mm)\nTru-Flate (automotive)  1/2 in  9/16 in (14.29 mm)  1/8 in (3.17 mm)\nARO (Milton A-style), NPT  1/4 in  5/16 in (7.94 mm)  5/16 in (7.94 mm)\nARO (Milton A-style), BSPT  1/4 in  5/16 in (7.94 mm)  3/8 in (9.52 mm)\nARO (Milton A-style), NPT  3/8 in  7/16 in (11.11 mm)  9/16 in (14.29 mm)\nEuropean (Milton V-style, Megaflow, NT 7.2 / DIN 7.2)  1/4 in  3/8 in (9.52 mm)  3/16 in (4.76 mm)\nJapanese  1/4 in  7/16 in (11.11 mm)  7/32 in (5.56 mm)\nSilverline bayonet (UK)  3/16 in  5/16 in (7.94 mm)  11/32 in (8.73 mm)\nLincoln  1/4 in  9/32 in (7.14 mm)  3/4 in (19.05 mm)\nSchrader quick-connect (twist lock)  1/4 in  5/16 in (7.94 mm)  3/4 in (19.05 mm)\nSchrader quick-connect (twist lock)  1/2 in  1/2 in (12.7 mm)  7/8 in (22.22 mm)\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Park Tool: Adapting the INF-2 for use with different air coupler standards: tip diameter (A) and tip length (B) of industrial, Tru-Flate, ARO, European, Japanese, Lincoln, Silverline and Schrader plugs — web — Maker article; numbers only — https://www.parktool.com/en-int/blog/repair-help/adapting-the-inf-2-for-use-with-different-air-coupler-standards\n- Wikipedia: Air-line fitting: coupler series (Milton letter, ARO, Parker, Euro), nominal diameters DN, and the standards each is listed under — web — Encyclopedia; names and standards only — https://en.wikipedia.org/wiki/Air-line_fitting\n- Hi-Line: 1/4 MPT Milton A-style, ARO 210 interchange series plugs, plated case-hardened steel (A-style = ARO 210; 300 psi, 34 SCFM) — web — Distributor listing; names only — https://hi-line.com/1-4-mpt-milton-a-style-aro-210-interchange-series-plugs-plated-case-hardened-steel/\n- Hi-Line: 1/4 MPT Milton T-style, Tru-Flate / Parker interchange series plugs, plated case-hardened steel — web — Distributor listing; names only — https://hi-line.com/1-4-fpt-milton-t-style-tru-flate-parker-interchange-series-plugs-plated-case-hardened-steel/\n- Guardair: Air fittings chart: Industrial Interchange (also M-style, I/M-style, Type-D) and High Flow (V-style, Megaflow, European interchange) plugs, 1/4 and 3/8 in — web — Maker chart; names only — https://guardair.com/pages/air-fittings-chart\n- Prevost: Safety quick couplings ISI 06, ISO 6150 B profile: G1/4, G3/8, G1/2 male thread couplers, 6 mm passage — web — Maker datasheet; numbers only — https://medias-prevost.nextpage.fr/Fiches%20produits%5CINT%5C69098_Parallel_male_thread_coupler_int.pdf\n- McMaster-Carr: Air hose couplings (quick-disconnect plugs and sockets) (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/air-hose-couplings\n- McMaster-Carr: ARO-style quick-disconnect hose fittings (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/products/hose-fittings/quick-disconnect-style~aro\n- McMaster-Carr: Quick-disconnect hose sockets (couplers) (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/quick-disconnect-hose-sockets\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=air-quick-coupler-plug-profiles\n",
 "sources": [
  {
   "publisher": "Park Tool",
   "title": "Adapting the INF-2 for use with different air coupler standards: tip diameter (A) and tip length (B) of industrial, Tru-Flate, ARO, European, Japanese, Lincoln, Silverline and Schrader plugs",
   "url": "https://www.parktool.com/en-int/blog/repair-help/adapting-the-inf-2-for-use-with-different-air-coupler-standards",
   "formats": [
    "web"
   ],
   "license": "Maker article; numbers only",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Wikipedia",
   "title": "Air-line fitting: coupler series (Milton letter, ARO, Parker, Euro), nominal diameters DN, and the standards each is listed under",
   "url": "https://en.wikipedia.org/wiki/Air-line_fitting",
   "formats": [
    "web"
   ],
   "license": "Encyclopedia; names and standards only",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Hi-Line",
   "title": "1/4 MPT Milton A-style, ARO 210 interchange series plugs, plated case-hardened steel (A-style = ARO 210; 300 psi, 34 SCFM)",
   "url": "https://hi-line.com/1-4-mpt-milton-a-style-aro-210-interchange-series-plugs-plated-case-hardened-steel/",
   "formats": [
    "web"
   ],
   "license": "Distributor listing; names only",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Hi-Line",
   "title": "1/4 MPT Milton T-style, Tru-Flate / Parker interchange series plugs, plated case-hardened steel",
   "url": "https://hi-line.com/1-4-fpt-milton-t-style-tru-flate-parker-interchange-series-plugs-plated-case-hardened-steel/",
   "formats": [
    "web"
   ],
   "license": "Distributor listing; names only",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Guardair",
   "title": "Air fittings chart: Industrial Interchange (also M-style, I/M-style, Type-D) and High Flow (V-style, Megaflow, European interchange) plugs, 1/4 and 3/8 in",
   "url": "https://guardair.com/pages/air-fittings-chart",
   "formats": [
    "web"
   ],
   "license": "Maker chart; names only",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Prevost",
   "title": "Safety quick couplings ISI 06, ISO 6150 B profile: G1/4, G3/8, G1/2 male thread couplers, 6 mm passage",
   "url": "https://medias-prevost.nextpage.fr/Fiches%20produits%5CINT%5C69098_Parallel_male_thread_coupler_int.pdf",
   "formats": [
    "web"
   ],
   "license": "Maker datasheet; numbers only",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "McMaster-Carr",
   "title": "Air hose couplings (quick-disconnect plugs and sockets) (free STEP/IGES per part, for your own design use; no redistribution)",
   "url": "https://www.mcmaster.com/air-hose-couplings",
   "formats": [
    "STEP",
    "IGES",
    "PDF"
   ],
   "license": "McMaster-Carr site terms: personal design use, no redistribution",
   "license_verified": false,
   "hosted": false
  },
  {
   "publisher": "McMaster-Carr",
   "title": "ARO-style quick-disconnect hose fittings (free STEP/IGES per part, for your own design use; no redistribution)",
   "url": "https://www.mcmaster.com/products/hose-fittings/quick-disconnect-style~aro",
   "formats": [
    "STEP",
    "IGES",
    "PDF"
   ],
   "license": "McMaster-Carr site terms: personal design use, no redistribution",
   "license_verified": false,
   "hosted": false
  },
  {
   "publisher": "McMaster-Carr",
   "title": "Quick-disconnect hose sockets (couplers) (free STEP/IGES per part, for your own design use; no redistribution)",
   "url": "https://www.mcmaster.com/quick-disconnect-hose-sockets",
   "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": [
  "camlock-couplings",
  "push-to-connect-fitting-sizes",
  "silicone-tube",
  "npt-thread-envelopes",
  "garden-hose-thread",
  "an-jic-37-degree-flare-fittings"
 ],
 "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 is the difference between M-style and T-style air couplers?",
   "a": "Same 1/4 in flow size but different tips: M (industrial) is 5/16 in diameter and 3/16 in long; T (Tru-Flate) is 3/8 in diameter and 1/16 in long (Park Tool). They do not interchange."
  },
  {
   "q": "Do M-style and A-style plugs interchange?",
   "a": "No. Both have a 5/16 in tip diameter, but the A (ARO) tip is longer: 5/16 in (NPT) or 3/8 in (BSPT) against 3/16 in for the industrial M tip."
  },
  {
   "q": "What is a 3/8 in H-style plug?",
   "a": "Milton's name for the 3/8 in industrial (Industrial Interchange) profile: 7/16 in tip diameter, 5/16 in tip length (Park Tool)."
  },
  {
   "q": "Which profile is ISO 6150 B?",
   "a": "Wikipedia lists ISO 6150 B against the US industrial 1/4, 3/8 and 1/2 in profiles (the M, H and G profiles); the standard's own drawing was not readable."
  }
 ],
 "files_license": null,
 "offers": [],
 "markdown": "https://xemstudio.com/objects/air-quick-coupler-plug-profiles/index.md"
}