Last reviewed: May 2026 · MLC editorial team · UK trade workshop perspective
Photo by Sandin Redzo on Pexels
A dial test indicator (DTI) is what you reach for when you need to dial in a four-jaw chuck or measure a parallel face to within two microns. Two brands dominate trade inspection work: Mitutoyo from Japan and Mahr from Germany. UK manufacturers Moore & Wright and Insize fill the budget tier with their offerings, which range from £50 to over £300 depending on features like accuracy and durability. In workshops across Britain, reliability and precision are non-negotiable - your DTI needs to withstand daily use while delivering consistent results. This article focuses on the best models available in 2026, covering everything from basic indicators for occasional tasks to high-precision instruments for demanding applications.
How we picked these
- Graduation: 0.01mm is workshop-standard. 0.002mm is required for precision inspection / aerospace bearing seat work.
- Range: 0.5-0.8mm covers most setup work. Plunger-style indicators offer larger range (1-10mm) at the cost of access angle.
- Stylus angle: pivoted-arm DTIs maintain accuracy as the stylus swings through ±20° from horizontal.
- Magnetic base compatibility: 8mm stem is the trade standard (works with Noga, Mitutoyo, Mahr magnetic bases).
- Calibration: UKAS-traceable calibration available on Mitutoyo and Mahr at £30-£60 extra.
Reviewed picks
Mitutoyo 513-404E
Price: £130-£180 | Best for: everyday workshop trade DTI
The Mitutoyo 513-404E is a stalwart dial test indicator for UK workshops priced between £130 and £180. Its robust jewelled bearing pivot ensures durability, while its 8mm stem fits any magnetic base. However, the 0.5mm range might be tight for some setups, making it best suited for everyday tasks where precision is key.
| Graduation | 0.01mm |
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| Range | 0.5mm |
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| Accuracy | ±10μm |
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| Stem | 8mm |
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| Dial size | 32mm |
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Pros
- Industry-reference brand
- 8mm stem fits any magnetic base
- Robust jewelled bearing pivot
Cons
- 0.5mm range tight for some setup
- Premium price
Check Mitutoyo 513-404E on Amazon UK →
Mahr Federal 800SI (0.6mm)
Price: £200-£280 | Best for: aerospace / precision inspection
The Mahr Federal 800SI (0.6mm) is a precision tool for aerospace and high-accuracy inspections. With a graduation of 0.002mm and ±2μm accuracy, it offers exceptional resolution and reliability. At £200 to £280, it's pricey compared to Mitutoyo models but boasts superior German engineering. However, it’s less common in UK workshops than its Japanese counterpart.
| Graduation | 0.002mm |
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| Range | 0.6mm |
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| Accuracy | ±2μm |
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| Stem | 8mm |
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| Dial size | 38mm |
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Pros
- 0.002mm graduation (2-micron resolution)
- Mahr German build quality
- ±2μm accuracy
Cons
- Higher cost than Mitutoyo
- Less common in UK trade than Mitutoyo
Check Mahr Federal 800SI (0.6mm) on Amazon UK →
Insize 2382-08
Price: £45-£75 | Best for: best budget dial test indicator
The Insize 2382-08 dial test indicator offers a range of 0.8mm with ±10μm accuracy at a price point of £45 to £75. Ideal for budget-conscious buyers, it delivers ±10μm precision for £50, more than Mitutoyo's range. However, its build quality isn't as robust as Mitutoyo or Mahr models, and the resale value is lower.
| Graduation | 0.01mm |
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| Range | 0.8mm |
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| Accuracy | ±10μm |
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| Stem | 8mm |
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| Dial size | 40mm |
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Pros
- £50 for ±10μm DTI
- 0.8mm range - wider than Mitutoyo
- Insize warranty in UK
Cons
- Less robust than Mitutoyo / Mahr
- Smaller resale value
Check Insize 2382-08 on Amazon UK →
Mitutoyo 513-426E
Price: £130-£170 | Best for: wider-range Mitutoyo for setup work
The Mitutoyo 513-426E dial test indicator offers a graduation of 0.01mm and a range of 0.8mm with an accuracy of ±10μm. Priced at £130 to £170, it's ideal for setup work needing a wider range than its counterparts. Its standout feature is the extended range, perfect for chuck alignment tasks. However, users note a slight increase in reading error when measuring at full capacity.
| Graduation | 0.01mm |
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| Range | 0.8mm |
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| Accuracy | ±10μm |
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| Stem | 8mm |
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| Dial size | 32mm |
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Pros
- 0.8mm range - better for chuck alignment
- Same Mitutoyo build as 513-404
- Universally accepted brand
Cons
- Slightly bigger reading-error at full range
- Premium price
Check Mitutoyo 513-426E on Amazon UK →
Tesa (Brown & Sharpe) TT60
Price: £180-£250 | Best for: Swiss-brand premium alternative to Mitutoyo
The Tesa TT60 is a precision tool with a 0.01mm graduation and 0.6mm range, accurate to ±10μm. Its 40mm dial offers better readability compared to competitors. At £180-£250, it's pricier than the Mitutoyo equivalent but boasts Swiss build quality and a reputable Tesa (Hexagon) name. However, its higher cost may deter some UK buyers due to limited trade recognition.
| Graduation | 0.01mm |
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| Range | 0.6mm |
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| Accuracy | ±10μm |
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| Stem | 8mm |
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| Dial size | 40mm |
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Pros
- Tesa (Hexagon) reputation
- Larger 40mm dial easier to read
- Swiss build quality
Cons
- Pricier than Mitutoyo equivalent
- Less UK trade recognition
Check Tesa (Brown & Sharpe) TT60 on Amazon UK →
Starrett 196A6Z set
Price: £350-£480 | Best for: US-spec trade set with magnetic base included
The Starrett 196A6Z dial test indicator offers a graduation of 0.001" and a range of 0.030", with a universal stem for flexibility. At £350-£480, it includes a magnetic base and extensions, housed in a wooden case. Ideal for those needing US-spec tools, though the imperial scale may require conversion for metric users.
| Graduation | 0.001" / 0.025mm |
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| Range | 0.030" / 0.75mm |
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| Stem | Universal |
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| Dial size | 1" |
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| Includes | Magnetic base + extensions |
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Pros
- Complete set - indicator + magnetic base + extensions
- Starrett brand recognition
- Wooden carry case
Cons
- Imperial scale unless converted
- Premium pricing
Check Starrett 196A6Z set on Amazon UK →
Recommendations at a glance
| Best overall (workshop trade) | Mitutoyo 513-404E - industry-standard 0.5mm range DTI |
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| Best precision / aerospace | Mahr Federal 800SI - 0.002mm graduation for 2-micron work |
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| Best budget pick | Insize 2382-08 - ±10μm dial indicator at sub-£75 |
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| Best wider-range Mitutoyo | 513-426E - 0.8mm range for chuck alignment |
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| Best Swiss alternative | Tesa TT60 - Swiss-grade build, 40mm dial |
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| Best complete set | Starrett 196A6Z - indicator + magnetic base + extensions |
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Related reference on MLC
Frequently asked questions
Plunger or dial test (lever) indicator?
Plunger indicators (Mitutoyo 2046S, Mahr 1083) have larger range (5-10mm typical) and read straight off the stem axis. Lever-arm DTIs are more compact, fit into bored holes and chucks, and maintain accuracy through a ±20° arc. Most workshops have one of each.
Do I need a UKAS-calibrated DTI?
For ISO 9001 / AS9100 audited work - yes. UKAS cert is £30-£60 extra and provides NPL-traceable accuracy at 0, 0.1, 0.2, 0.3, 0.4mm. For general workshop setup work, a manufacturer-stated accuracy is sufficient.
Mitutoyo or Mahr - which is better?
Mitutoyo dominates UK and Asian inspection rooms with wider service network. Mahr is the German aerospace / precision standard. Class-for-class they're equivalent - pick by which brand your colleagues / clients recognise.
What's the difference between 0.01mm and 0.002mm graduation?
0.01mm is workshop-standard (10 microns) and adequate for chuck alignment, parallel-face setup, and general inspection. 0.002mm (2 microns) is needed for aerospace bearing seats, motorsport crank measurement, and inspection-room work requiring sub-5 micron resolution.
Will a budget Insize / Aliexpress DTI hold its accuracy?
Insize at £50 holds ±10μm if treated carefully - a fall on a steel bench can shift the calibration. Unbranded Chinese DTIs at £15-£25 typically read ±20-30μm and lose accuracy within months. For one-off setup work the Insize is fine; for inspection work that gets re-checked, buy the Mitutoyo.
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