Independent comparisons. We may earn from shop links. More info

Square vs round strimmer line at 2.4 mm

Updated: October 2026

The head already takes 2.4 mm, and a square reel is being sold as the upgrade. Square vs round strimmer line, at the same stated diameter, is the edge and the corner, not a new size. Round feeds. The square corner is wider than the side. Star has five edges, and it is not a quiet square. Peter F. compared the amazon.co.uk packs in the [2.4 mm strimmer line comparison](/hub/lawn-and-garden-equipment/2-4mm-strimmer-line), captured on 19 October 2026, plus Stihl UK and Oregon UK wording. We did not run a lab cut. A qualifying purchase can earn a commission at no extra cost to you. Length stays on the [2.4 mm strimmer line buying guide](/hub/lawn-and-garden-equipment/2-4mm-strimmer-line/sub/2-4mm-strimmer-line-buying-guide).

The head already takes 2.4 mm, and a square reel is being sold as the upgrade. Square vs round strimmer line, at the same stated diameter, is the edge and the corner, not a new size. Round feeds.

Our top picks

Viabrico Viabrico square 100 m

Best overall

Viabrico Viabrico square 100 m
9.2/10about £10.99
View offer
Oregon Oregon Nylium star 90 m

Alternative

Oregon Oregon Nylium star 90 m
8.2/10about £25.76
View offer
Oregon Oregon round 15 m

Best value

Oregon Oregon round 15 m
6.4/10about £5.99
View offer
On this page
  1. 1.Round is the cord the head was usually supplied with
  2. 2.Square means the side, and the corner is wider
  3. 3.Star means five edges, and Nylium is a material claim
  4. 4.What the reviews actually fought about
  5. 5.When round, when square, when star

Round is the cord the head was usually supplied with

Round 2.4 mm is a circular section. The width the eyelet sees is the width on the packet. ManoMano’s UK guide says round unwinds easily and the cutting angle does not change as it wears, which is why it is the usual lawn-edge cord. In this set that shape is Oregon’s 15 m doughnut at about £5.99, the 88 m pack at about £16.46, and the yellow 264 m roll at about £31.33. The 15 m and 88 m listings share one star line, 4.3 from 14,156. If the job is a weekly edge, stay with round. Move to a square only when the grass is thicker and the eyelet has room for the corner.

Square means the side, and the corner is wider

On square cord the stated 2.4 mm is one side. The diagonal is longer. Zeqeey prints side 2.4 mm and a diagonal of about 3.4 mm, about 100 m at about £14.99. Viabrico’s 100 m square at about £10.99 and Stihl’s 253 m square at about £33.92 state the side and do not print a diagonal. Do not paste 3.4 mm onto their packets. Stihl UK calls square more aggressive than round for thick woody grass, and mentions a brush knife. That simile is not a blade test. ManoMano says square hacks and should stay off wall render. A Zeqeey review snaps near a wall. One AutoCut C 3-2 owner says square is the maximum that head will take.
Viabrico Viabrico square 100 m

Testsieger

Viabrico Viabrico square 100 m
9.2/10about £10.99
View offer

Star means five edges, and Nylium is a material claim

Star line here has five edges. Oregon’s UK page for Nylium Star, part 104883E, says aluminium particles resist welding when the head heats. That is maker wording, not a percentage for every star reel. The 90 m listing at about £25.76 is the one whose item type says Nylium. The 360 m listing, model 104885E at about £53.53, names the particles and does not say Nylium in the title. The 332 m star does not mention them. YAMAKATO’s orange 60 m is pentagonal, not Nylium, and 12 reviews are too small to treat it as the same product. Do not hang a 27% efficiency claim, or 10% quieter, on these ASINs. One DeWalt owner says the five-edge line was substantially louder.

What the reviews actually fought about

The saved texts argue about feed, noise, melt, and walls. They are not a ranked cut. Zeqeey’s square is stiff, snaps by a fence, and jammed one Husqvarna spool. Stihl’s 253 m square is praised for thick farm grass, then marked down when a Honda petrol head melted it. Oregon’s 90 m star is praised through brambles, with a shorter life, and returned after breaks on ordinary nettles. Most of the 332 m sample is not from the United Kingdom. Choose a star only when the bullet names aluminium particles, if that welding claim is what you want. Length does not change the corner.

When round, when square, when star

Stay on round 2.4 mm for a lawn edge. Move to square only when the grass is thicker and you have checked the corner, not the printed side. Choose five edges when the bullet names aluminium particles.

Common questions

Is 2.4 mm square the same thickness at the eyelet as 2.4 mm round?
No. The 2.4 mm on a square is the side. The corner is wider. Zeqeey prints a diagonal of about 3.4 mm. Round 2.4 mm is 2.4 mm across. An eyelet that only just accepts the round line can refuse the square. Viabrico and the Stihl 253 m reel do not print their own diagonal, so you still test the eyelet. Do not paste Zeqeey’s 3.4 mm onto their packets.
What are the five edges for?
Oregon presents five edges as a neater cut than a plain round, and aluminium particles, where the bullet names them, as a way to resist welding in a hot head. That is the maker’s claim for Nylium star. It is not five measured cuts, and it is not printed on the 332 m star. One review also calls five edges louder than stock DeWalt line.
Is YAMAKATO’s orange star the same as Oregon Nylium?
No. YAMAKATO is a pentagonal 60 m pack at about £10.99 with a cutter and 12 reviews. Oregon Nylium star in this set is the 90 m listing, model 104883E, whose bullet names nylon with aluminium particles. The orange colour does not make them the same line. Twelve ratings are too small to borrow Oregon’s review file.
Will square or star make the strimmer louder?
One owner of the 90 m five-edge line says it is substantially louder than DeWalt stock line and blames the shape. A UK note on the 332 m star calls it a bit noisy next to Stihl CF3 Pro. Viabrico’s square changed the sound for one buyer. Those are reviews, not a decibel test. Do not expect a quieter machine because a listing says star.
Why did a square melt in one Honda head?
One UK review of the Stihl 253 m square says it melted and stuck inside a Honda petrol head, and that round worked better there. A 90 m star review says that line sometimes starts to melt. Heat, a tight wind, and a shape the head is struggling to feed are the pattern. It is not proof that every Honda head rejects every square. Go back to round if yours has already stuck.

Related pages

Best 2.4 mm strimmer line

How to fit strimmer line

2.4 mm strimmer line for thick weeds

2.4 mm strimmer line

2.4 mm strimmer line: what to check before you buy

Sources

Shelf prices, star ratings and review counts are the amazon.co.uk figures captured on 19 October 2026. The other pages are public UK guidance on line profile, soak advice, vibration and garden safety.

  1. Stihl UK square 2.4 mm mowing line (retrieved 19 October 2026)
  2. Oregon UK Nylium Star 2.4 mm 90 m (retrieved 19 October 2026)
  3. Oregon profile map (retrieved 19 October 2026)
  4. ManoMano UK trimmer line buying guide (retrieved 19 October 2026)
  5. HSE chain flails and brush cutters (retrieved 19 October 2026)
  6. HSE INDG480 hand-arm vibration (retrieved 19 October 2026)
  7. RHS hedgehog-friendly gardening (retrieved 19 October 2026)
  8. GOV.UK noise nuisances (retrieved 19 October 2026)