Tubing size
Metric 4/6 and 4/7 mm drip microtubing: what makers state
Claber sells 4-6 mm tube as 1/4 in; AquaGrow's 4/7 mm tee asks buyers to confirm the actual sizes. What is stated, and what is not, for metric microtubing.
Also listed as 4/7 mm, 4x7 mm, 4-6 mm
Short answer
Metric microtubing is named by millimeters, and the names do not settle fit. Claber sells a 4-6 mm tube labeled 1/4 in, and AquaGrow's 4/7 mm barbed tee tells buyers to confirm the actual inner and outer dimensions and lists no pressure rating. Antelco's SPEC Drip has an outlet barb for 4 mm ID tubing. See joining metric tubing to US parts.
Key facts
- Outside diameter
- Claber names the family 4-6 mm. AquaGrow gives no number and tells buyers to confirm the actual outer dimension[2][1]
- Inside diameter
- Antelco SPEC Drip: outlet barb for 4 mm ID tubing. AquaGrow tells buyers to confirm the actual inner dimension[4][1]
- Tubing makers list at this size
- Claber 90371: 5 m polyethylene feeding tube labeled 1/4 in, 4-6 mm[3]
- Maker pressure rating
- None stated: AquaGrow's 4/7 mm tee asks buyers to confirm the pressure rating[1]
- Compression fittings for this OD
- Not confirmedNo compression fitting for metric microtubing is in our sources.
- Locking-nut and universal fittings
- Not confirmedNo locking-nut fitting for metric microtubing is in our sources.
- Barbed fittings
- AquaGrow AG-4/7WG-3T barbed tee for 4/7 mm tubing, with no numeric barb size on the listing[1]
- Reducers and adapters
- Not confirmedNo source shows an adapter between 4/7 mm tubing and US 1/4 in parts.
- End closures, plugs and stakes
- Not confirmedNo plug or stake listed for metric microtubing is in our sources.
- How to identify it
- Read the kit or bag label for a millimeter size. Then cut a fresh, square end and measure the OD with calipers in millimeters; AquaGrow itself tells buyers to confirm actual inner and outer dimensions. Steps: [how to measure drip tubing](/guides/how-to-measure-drip-tubing); lookup: [tubing size finder](/tools/drip-tubing-size-finder)[1]
- Maker-page conflicts
- Claber calls its 4-6 mm tube 1/4 in, while the US 1/4 in poly in our sources is .170 x .250 in (about 4.3 x 6.35 mm by arithmetic)[3][5]The arithmetic is a conversion, not a fit allowance.
- Not confirmed
- Not confirmedNo source gives the OD of 4/7 mm tubing as a number, a pressure rating, or a confirmed join to US 1/4 in parts. Antelco's US and Canada availability is not established.
Watch out for
- AquaGrow's own 4/7 mm listing tells buyers to confirm actual inner and outer dimensions before ordering, and lists no pressure rating.
- Claber sells its 4-6 mm tube as 1/4 in. The label does not show it matches .170 x .250 in US tubing.
- Antelco's SPEC Drip outlet is for 4 mm ID tubing, but Antelco announced it on its EU site and states no US or Canada availability.
Questions
Is 4/7 mm tubing the same as 1/4 in?
Not established. Claber labels a 4-6 mm tube 1/4 in, while US 1/4 in poly in our sources is .170 x .250 in. Measure both before you join them.[3][5]
What pressure can 4/7 mm fittings take?
AquaGrow's 4/7 mm tee lists no pressure rating and asks buyers to confirm the rating, clamp requirement and connection layout.[1]
Do any emitters use 4 mm ID tubing?
Antelco describes its SPEC Drip as having an outlet barb for 4 mm ID tubing, in 2, 4 and 8 L/h flows. Its US and Canada availability is not established.[4]