Klein Tools CL390 clamp meter
Checked 2026-10-17 against Klein Tools' US product page by Rob, licensed electrician
The Klein Tools CL390 is a clamp meter, sold on its own. Klein Tools publishes CAT III 600 V safety rating, 400 A AC current (max range), 400 A DC current (max range), 600 V AC voltage (max range). In the box: Clamp Meter, Carrying Case, Instructions, Test Leads, Thermocouple, Batteries. Source: Klein Tools' US product page, checked 2026-10-17.
Key specs
- Safety rating (IEC 61010 CAT)
- CAT III 600 V
- AC current, max range
- 400 A
- DC current, max range
- 400 A
- AC voltage, max range
- 600 V
- DC voltage, max range
- 600 V
- True-RMS
- Yes
- Jaw opening
- 1.6 inJoint 2nd widest of the 11 clamp meters we cover
- Display resolution
- 4,000 counts
- Batteries (cells)
- 3 x AAA
Not on Klein Tools' US product page for the CL390: Warranty. We do not guess.
In the box
- IncludedClamp meter: Clamp Meter
- IncludedTest leads: Test Leads
- IncludedBatteries: Batteries
- IncludedCase or holster: Carrying Case
- IncludedAlso in the box: Thermocouple
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Find CL390 prices on Amazon Find CL390 prices at Acme Tools Find CL390 prices at eBay New tab, US retailers. Search results open where no exact listing is on file. Check the listing says CL390; marketplace sellers vary.- US retailer, ships from the US
- Free shipping over $199
- Family owned since 1948
- Acme Tools, as published on its site, checked 2026-10-17
Compared with
All specs
| Safety rating (IEC 61010 CAT) | CAT III 600 V |
| AC current, max range | 400 A |
| DC current, max range | 400 A |
| AC voltage, max range | 600 V |
| DC voltage, max range | 600 V |
| True-RMS | Yes |
| Jaw opening | 1.6 in |
| Display resolution | 4,000 counts |
| Batteries (cells) | 3 x AAA |
| Resistance, max range | 40 MΩ |
| Capacitance, max range | 4,000 μF |
| Frequency, max range | 60 kHz |
| Temperature measurement | -40° - 1,832°F (-40° - 1,000°C) |
| Non-contact voltage detection | Yes |
| Drop protection | 6.6 ft (2 m) |
| Size | 8.45 x 3.5 x 1.5 in (L x W x H) |
| UPC barcode | 092644692871 |
Ratings are Klein Tools' published figures from its US product page, listed under Sources. Anything not on that page is left out rather than guessed. Check this against another model.
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Quick answers
What is the CL390's safety (CAT) rating?
Klein Tools rates it CAT III 600 V. CAT IV covers the service entrance and utility side, CAT III distribution-level circuits such as panels and feeders; the lower of the meter's and the test leads' ratings is the one that applies. See our CAT ratings guide.
Does the CL390 measure DC current?
Yes: Klein Tools lists a DC current range up to 400 A.
Is the CL390 true-RMS?
Yes, Klein Tools lists it as true-RMS, so readings on non-sinusoidal loads (drives, dimmers, electronic ballasts) are not averaged.
What batteries does the CL390 use?
3 x AAA (dry cells; no tool battery platform).
Does the CL390 come with test leads?
Yes: Test Leads.
Owner reviews
Read the owner reviews on KleinTools.com
Manuals and official documents
Sources
- Klein Tools US product page CL390, retrieved 2026-10-17
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Researched by Rob, licensed electrician (Australia). Found an error? Tell us.
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