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Push-to-connect pneumatic fittings: tube OD 4 to 12 mm and 1/8 to 1/2 in with the thread sizes offered

Which tube sizes and thread sizes do push-to-connect fittings come in? · Standard part · basis: SMC KQ2H male connector series listings (metric and NPT inch ranges); numbers only

Also called: 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

Exact dimensions. True size, with no printing tolerance added.

sizes
12 in table

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.

Push-to-connect pneumatic fittings: tube OD 4 to 12 mm and 1/8 to… size chart

tube ODmale threads offered (SMC KQ2H)
4 mmR1/8, R1/4, M5, M6
6 mmR1/8, R1/4, R3/8, M5, M6
8 mmR1/8, R1/4, R3/8
10 mmR1/8, R1/4, R3/8, R1/2
12 mmR1/4, R3/8, R1/2
16 mmR3/8, R1/2
1/8 inNPT 1/16, 1/8, 1/4
5/32 inNPT 1/16, 1/8, 1/4
1/4 inNPT 1/16, 1/8, 1/4, 3/8
5/16 inNPT 1/8, 1/4, 3/8
3/8 inNPT 1/8, 1/4, 3/8, 1/2
1/2 inNPT 1/4, 3/8, 1/2

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

SMC Pneumatics (distributor)KQ2H male connector, metricwebPublisher's page; dimensions are facts
SMC Pneumatics (distributor)KQ2H male connector, inch tube, NPTwebPublisher's page; dimensions are facts

Xem scan

File coming

No downloadable true-size file yet: the published figures do not fix the whole shape, and Xem never guesses a number. A measured scan is planned; request it and it moves up.

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Plain text: sheet.txt · JSON: /api/geometry?object=push-to-connect-fitting-sizes

length
Schematic, not to scale.

Fits with

PU pneumatic tube 4 to 12 mm OD (push-fit sizes), isometric render of a generated part
PU pneumatic tube 4 to 12 mm OD (push-fit sizes)5 sizes★ 5 files
Push-fit fitting envelopes: 4 / 6 / 8 mm tube, G1/8 and G1/4 thread stubs, isometric render of a generated part
Push-fit fitting envelopes: 4 / 6 / 8 mm tube, G1/8 and G1/4 thread stubs4 sizes★ 4 files
NPT male thread envelopes 1/8 to 1 in (ASME B1.20.1), isometric render of a generated part
NPT male thread envelopes 1/8 to 1 in (ASME B1.20.1)6 sizes★ 6 files
BSP (G) male thread envelopes 1/8 to 1 in (ISO 228-1), isometric render of a generated part
BSP (G) male thread envelopes 1/8 to 1 in (ISO 228-1)6 sizes★ 6 files
Hose barbs for 2, 3, 4, 6 and 8 mm ID tube, isometric render of a generated part
Hose barbs for 2, 3, 4, 6 and 8 mm ID tube5 sizes★ 5 files

Questions

Does 1/4 in tube fit a 6 mm push-in fitting?

No: 1/4 in is 6.35 mm. It does not seal reliably in a 6 mm fitting; use the matching inch fitting.

What threads come on 6 mm push-in male connectors?

SMC KQ2H 6 mm: R1/8, R1/4, R3/8, M5 and M6.