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 Source: Xem Studio, https://xemstudio.com/objects/air-quick-coupler-plug-profiles/ (sheet CC BY 4.0) 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 Catalog version: 2026-10-20 Sizes: see table below - 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. profile (Milton letter) flow size tip diameter A tip length B 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) Files elsewhere (not hosted by Xem Studio; license as stated by the publisher): - 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 - 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 - 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/ - 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/ - 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 - 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 - 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 - 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 - 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 No true-size file yet: the published figures do not fix the whole shape; a measured scan is planned. 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